485BPOS

Securities Act of 1933 Registration No. 002-69972

Investment Company Act of 1940 Registration No. 811-03114

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM N-1A

REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933 [X]

[ ] Pre-Effective Amendment No.  ______

[X] Post-Effective Amendment No.  158

and

REGISTRATION STATEMENT UNDER THE INVESTMENT COMPANY ACT OF 1940 [X]

[X] Amendment No.  158

Fidelity Select Portfolios

 (Exact Name of Registrant as Specified in Charter)

245 Summer Street, Boston, Massachusetts 02210

(Address of Principal Executive Offices)(Zip Code)

Registrant’s Telephone Number: 617-563-7000

Cynthia Lo Bessette, Secretary

245 Summer Street

Boston, Massachusetts 02210

(Name and Address of Agent for Service)

It is proposed that this filing will become effective immediately upon filing pursuant to paragraph (b) of Rule 485.

EXHIBIT INDEX

Exhibit	Exhibit No.
XBRL Instance Document	EX-101.INS
XBRL Taxonomy Extension Schema Document	EX-101.SCH
XBRL Taxonomy Extension Calculation Linkbase Document	EX-101.CAL
XBRL Taxonomy Extension Definition Linkbase Document	EX-101.DEF
XBRL Taxonomy Extension Labels Linkbase Document	EX-101.LAB
XBRL Taxonomy Extension Presentation Linkbase Document	EX-101.PRE

SIGNATURES

Pursuant to the requirements of the Securities Act of 1933 and the Investment Company Act of 1940, the Registrant certifies that it meets all of the requirements for the effectiveness of this Registration Statement pursuant to Rule 485(b) under the Securities Act of 1933 and has duly caused this Post-Effective Amendment No. 158 to the Registration Statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Boston, and Commonwealth of Massachusetts, on the 15th day of May 2020.

Fidelity Select Portfolios
By	/s/Stacie M. Smith
	Stacie M. Smith, President

Pursuant to the requirements of the Securities Act of 1933, this Registration Statement has been signed below by the following persons in the capacities and on the dates indicated.

(Signature)		(Title)	(Date)
/s/Stacie M. Smith		President and Treasurer	May 15, 2020
Stacie M. Smith		(Principal Executive Officer)
/s/John J. Burke III		Chief Financial Officer	May 15, 2020
John J. Burke III		(Principal Financial Officer)
/s/James C. Curvey	*	Trustee	May 15, 2020
James C. Curvey
/s/Dennis J. Dirks	*	Trustee	May 15, 2020
Dennis J. Dirks
/s/Donald F. Donahue	*	Trustee	May 15, 2020
Donald F. Donahue
/s/Alan J. Lacy	*	Trustee	May 15, 2020
Alan J. Lacy
/s/Ned C. Lautenbach	*	Trustee	May 15, 2020
Ned C. Lautenbach
/s/Joseph Mauriello	*	Trustee	May 15, 2020
Joseph Mauriello
/s/Cornelia M. Small	*	Trustee	May 15, 2020
Cornelia M. Small
/s/Garnett A. Smith	*	Trustee	May 15, 2020
Garnett A. Smith
/s/David M. Thomas	*	Trustee	May 15, 2020
David M. Thomas
/s/Michael E. Wiley	*	Trustee	May 15, 2020
Michael E. Wiley

*	By:	/s/Megan C. Johnson
		Megan C. Johnson, pursuant to powers of attorney dated March 2, 2018 and January 1, 2019 and filed herewith.

POWER OF ATTORNEY

We, the undersigned Directors or Trustees, as the case may be, of the following investment companies:

Fidelity Advisor Series I Fidelity Advisor Series VII Fidelity Advisor Series VIII Fidelity Beacon Street Trust Fidelity Capital Trust Fidelity Central Investment Portfolios LLC Fidelity Commonwealth Trust Fidelity Commonwealth Trust II Fidelity Concord Street Trust Fidelity Congress Street Fund Fidelity Contrafund Fidelity Covington Trust Fidelity Destiny Portfolios Fidelity Devonshire Trust Fidelity Exchange Fund Fidelity Financial Trust Fidelity Hanover Street Trust Fidelity Hastings Street Trust Fidelity Investment Trust Fidelity Magellan Fund Fidelity Mt. Vernon Street Trust Fidelity Puritan Trust Fidelity Securities Fund Fidelity Select Portfolios Fidelity Summer Street Trust Fidelity Trend Fund Variable Insurance Products Fund Variable Insurance Products Fund II Variable Insurance Products Fund III Variable Insurance Products Fund IV

in addition to any other investment company for which Fidelity Management & Research Company (“FMR”) or an affiliate acts as investment adviser and for which the undersigned individuals serve as Directors or Trustees (collectively, the “Funds”), hereby revoke all previous powers of attorney we have given to sign and otherwise act in our names and behalf in matters involving any investment company for which FMR or an affiliate acts as investment adviser and hereby constitute and appoint Thomas C. Bogle, John V. O’Hanlon, Robert W. Helm, Megan C. Johnson, and Anthony H. Zacharski, each of them singly, our true and lawful attorneys-in-fact, with full power of substitution, and with full power to each of them, to sign for us and in our names in the appropriate capacities, all Registration Statements of the Funds on Form N-1A, or any successors thereto, any and all subsequent Amendments, Pre-Effective Amendments, or Post-Effective Amendments to said Registration Statements or any successors thereto, and any supplements or other instruments in connection therewith, and generally to do all such things in our names and behalf in connection therewith as said attorneys–in-fact deem necessary or appropriate, to comply with the provisions of the Securities Act of 1933 and the Investment Company Act of 1940, and all related requirements of the Securities and Exchange Commission.  We hereby ratify and confirm all that said attorneys-in-fact or their substitutes may do or cause to be done by virtue hereof.  This power of attorney is effective for all documents filed on or after January 1, 2019.

WITNESS our hands on this first day of January 2019.

/s/James C. Curvey	/s/Joseph Mauriello
James C. Curvey	Joseph Mauriello
/s/Dennis J. Dirks	/s/Cornelia M. Small
Dennis J. Dirks	Cornelia M. Small
/s/Donald F. Donahue	/s/Garnett A. Smith
Donald F. Donahue	Garnett A. Smith
/s/Alan J. Lacy	/s/David M. Thomas
Alan J. Lacy	David M. Thomas
/s/Ned C. Lautenbach
Ned C. Lautenbach

POWER OF ATTORNEY

I, the undersigned Director or Trustee, as the case may be, of the following investment companies:

Fidelity Advisor Series I Fidelity Advisor Series VII Fidelity Beacon Street Trust Fidelity Capital Trust Fidelity Central Investment Portfolios LLC Fidelity Commonwealth Trust Fidelity Commonwealth Trust II Fidelity Congress Street Fund Fidelity Contrafund Fidelity Covington Trust Fidelity Destiny Portfolios Fidelity Devonshire Trust
Fidelity Exchange Fund Fidelity Financial Trust Fidelity Hanover Street Trust Fidelity Hastings Street Trust Fidelity Magellan Fund Fidelity Mt. Vernon Street Trust Fidelity Select Portfolios Fidelity Summer Street Trust Fidelity Trend Fund Variable Insurance Products Fund II Variable Insurance Products Fund III Variable Insurance Products Fund IV

in addition to any other investment company for which Fidelity Management & Research Company (“FMR”) or an affiliate acts as investment adviser and for which the undersigned individual serves as Director or Trustee (collectively, the “Funds”), hereby revokes all previous powers of attorney I have given to sign and otherwise act in my name and behalf in matters involving any investment company for which FMR or an affiliate acts as investment adviser and hereby constitute and appoint Thomas C. Bogle, John V. O’Hanlon, Robert W. Helm, Megan C. Johnson, and Anthony H. Zacharski, each of them singly, my true and lawful attorneys-in-fact, with full power of substitution, and with full power to each of them, to sign for me and in my name in the appropriate capacities, all Registration Statements of the Funds on Form N-1A, or any successors thereto, any and all subsequent Amendments, Pre-Effective Amendments, or Post-Effective Amendments to said Registration Statements or any successors thereto, and any supplements or other instruments in connection therewith, and generally to do all such things in my name and behalf in connection therewith as said attorneys–in-fact deem necessary or appropriate, to comply with the provisions of the Securities Act of 1933 and the Investment Company Act of 1940, and all related requirements of the Securities and Exchange Commission.  I hereby ratify and confirm all that said attorneys-in-fact or their substitutes may do or cause to be done by virtue hereof.  This power of attorney is effective for all documents filed on or after March 2, 2018.

WITNESS our hands on this second day of March 2018.

/s/ Michael E. Wiley    

Michael E. Wiley

XML

Label	Element	Value
Risk/Return:	rr_RiskReturnAbstract
Registrant Name	dei_EntityRegistrantName	FIDELITY SELECT PORTFOLIOS
Prospectus Date	rr_ProspectusDate	Apr. 29, 2020
Document Creation Date	dei_DocumentCreationDate	Apr. 24, 2020

XML

Label

Element

Value

Risk/Return:

rr_RiskReturnAbstract

Registrant Name

dei_EntityRegistrantName

FIDELITY SELECT PORTFOLIOS

Prospectus Date

rr_ProspectusDate

Apr. 29, 2020

02.28 Select Portfolios: Group 1 Consumer Discretionary Sector Combo PRO-16 | Leisure Portfolio

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: bold 12pt Arial, Helvetica, sans-serif;">Fund:<br/>Leisure Portfolio</p>

Objective [Heading]

rr_ObjectiveHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks capital appreciation.

Expense [Heading]

rr_ExpenseHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

Shareholder Fees Caption [Text]

rr_ShareholderFeesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

(fees paid directly from your investment)

rr_ShareholderFeeOther

none

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

Portfolio Turnover [Text Block]

rr_PortfolioTurnoverTextBlock

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 53% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

53.00%

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Strategy [Heading]

rr_StrategyHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in the design, production, or distribution of goods or services in the leisure industries.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

Strategy Portfolio Concentration [Text]

rr_StrategyPortfolioConcentration

<font style="FONT-FAMILY: Times New Roman" size="3">Normally investing at least 80% of assets in securities of companies principally engaged in the design, production, or distribution of goods or services in the leisure industries.</font>

Risk [Heading]

rr_RiskHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Leisure Industry Concentration. The leisure industry can be significantly affected by the performance of the overall economy, changing consumer tastes, intense competition, and government regulation.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

Risk Lose Money [Text]

rr_RiskLoseMoney

<font style="FONT-FAMILY: Times New Roman" size="3">You could lose money by investing in the fund.</font>

Risk Nondiversified Status [Text]

rr_RiskNondiversifiedStatus

<font style="FONT-FAMILY: Times New Roman" size="3">In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.</font>

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

<font style="FONT-FAMILY: Times New Roman" size="3">An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</font>

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

<font style="FONT-FAMILY: Times New Roman" size="3">The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time.</font>

Performance Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

<font style="FONT-FAMILY: Times New Roman" size="3">www.fidelity.com </font>

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

<font style="FONT-FAMILY: Times New Roman" size="3">Past performance (before and after taxes) is not an indication of future performance.</font>

Bar Chart [Heading]

rr_BarChartHeading

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	15.87%	March 31, 2012
Lowest Quarter Return	-14.08%	September 30, 2011
Year-to-Date Return	-32.67%	March 31, 2020

Performance Table Heading

rr_PerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

<font style="FONT-FAMILY: Times New Roman" size="3">After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes.</font>

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

<font style="FONT-FAMILY: Times New Roman" size="3">The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan).</font>

Performance Table Explanation after Tax Higher

rr_PerformanceTableExplanationAfterTaxHigher

<font style="FONT-FAMILY: Times New Roman" size="3">Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.</font>

Performance Table Narrative

rr_PerformanceTableNarrativeTextBlock

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

02.28 Select Portfolios: Group 1 Consumer Discretionary Sector Combo PRO-16 | Leisure Portfolio | Leisure Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Management fee

rr_ManagementFeesOverAssets

0.54%

Distribution and/or Service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

none

Other expenses

rr_OtherExpensesOverAssets

0.22%

Total annual operating expenses

rr_ExpensesOverAssets

0.76%

1 year

rr_ExpenseExampleYear01

$ 78

3 years

rr_ExpenseExampleYear03

243

5 years

rr_ExpenseExampleYear05

422

10 years

rr_ExpenseExampleYear10

$ 942

2010

rr_AnnualReturn2010

37.88%

2011

rr_AnnualReturn2011

5.85%

2012

rr_AnnualReturn2012

11.40%

2013

rr_AnnualReturn2013

41.72%

2014

rr_AnnualReturn2014

8.33%

2015

rr_AnnualReturn2015

3.32%

2016

rr_AnnualReturn2016

6.35%

2017

rr_AnnualReturn2017

29.05%

2018

rr_AnnualReturn2018

(7.15%)

2019

rr_AnnualReturn2019

28.76%

Year to Date Return, Label

rr_YearToDateReturnLabel

Year-to-Date Return

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Mar. 31, 2020

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

(32.67%)

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Highest Quarter Return

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Mar. 31, 2012

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

15.87%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Lowest Quarter Return

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Sep. 30, 2011

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(14.08%)

02.28 Select Portfolios: Group 1 Consumer Discretionary Sector Combo PRO-16 | Leisure Portfolio | Return Before Taxes | Leisure Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Leisure Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return Before Taxes</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

28.76%

Past 5 years

rr_AverageAnnualReturnYear05

11.13%

Past 10 years

rr_AverageAnnualReturnYear10

15.52%

02.28 Select Portfolios: Group 1 Consumer Discretionary Sector Combo PRO-16 | Leisure Portfolio | After Taxes on Distributions | Leisure Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Leisure Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

26.90%

Past 5 years

rr_AverageAnnualReturnYear05

9.28%

Past 10 years

rr_AverageAnnualReturnYear10

13.96%

02.28 Select Portfolios: Group 1 Consumer Discretionary Sector Combo PRO-16 | Leisure Portfolio | After Taxes on Distributions and Sales | Leisure Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Leisure Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions and Sale of Fund Shares</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

18.34%

Past 5 years

rr_AverageAnnualReturnYear05

8.59%

Past 10 years

rr_AverageAnnualReturnYear10

12.79%

02.28 Select Portfolios: Group 1 Consumer Discretionary Sector Combo PRO-16 | Leisure Portfolio | S&P 500® Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

31.49%

Past 5 years

rr_AverageAnnualReturnYear05

11.70%

Past 10 years

rr_AverageAnnualReturnYear10

13.56%

02.28 Select Portfolios: Group 1 Consumer Discretionary Sector Combo PRO-16 | Leisure Portfolio | MSCI U.S. IMI Consumer Services 25-50 Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

28.29%

Past 5 years

rr_AverageAnnualReturnYear05

13.77%

Past 10 years

rr_AverageAnnualReturnYear10

15.96%

XML

Total

02.28 Select Portfolios: Group 4 Financials Sector Combo PRO-15 | Insurance Portfolio

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: bold 12pt Arial, Helvetica, sans-serif;">Fund:<br/>Insurance Portfolio</p>

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

The fund seeks capital appreciation.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

Shareholder Fees {- Insurance Portfolio}	02.28 Select Portfolios: Group 4 Financials Sector Combo PRO-15 Insurance Portfolio USD ($)
(fees paid directly from your investment)	none

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Annual Operating Expenses {- Insurance Portfolio}	02.28 Select Portfolios: Group 4 Financials Sector Combo PRO-15 Insurance Portfolio Insurance Portfolio-Default
Management fee	0.53%
Distribution and/or Service (12b-1) fees	none
Other expenses	0.28%
Total annual operating expenses	0.81%

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Expense Example {- Insurance Portfolio}	02.28 Select Portfolios: Group 4 Financials Sector Combo PRO-15 Insurance Portfolio Insurance Portfolio-Default USD ($)
1 year	$ 83
3 years	259
5 years	450
10 years	$ 1,002

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 28% of the average value of its portfolio.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in underwriting, reinsuring, selling, distributing, or placing of property and casualty, life, or health insurance.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Insurance Industry Concentration. The insurance industry is subject to extensive government regulation and can be significantly affected by interest rates, general economic conditions, and price and marketing competition. Different segments of the industry can be significantly affected by natural disasters, mortality and morbidity rates, and environmental clean-up.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	14.69%	March 31, 2013
Lowest Quarter Return	-17.60%	September 30, 2011
Year-to-Date Return	-29.18%	March 31, 2020

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

Average Annual Total Returns{- Insurance Portfolio} - 02.28 Select Portfolios: Group 4 Financials Sector Combo PRO-15 - Insurance Portfolio	Past 1 year	Past 5 years	Past 10 years
Insurance Portfolio-Default | Return Before Taxes	30.03%	10.24%	13.37%
Insurance Portfolio-Default | After Taxes on Distributions	27.86%	7.60%	11.36%
Insurance Portfolio-Default | After Taxes on Distributions and Sales	19.13%	7.74%	10.75%
S&P 500® Index(reflects no deduction for fees, expenses, or taxes)	31.49%	11.70%	13.56%
MSCI U.S. IMI Insurance 25-50 Index(reflects no deduction for fees, expenses, or taxes)	28.44%	10.78%	13.45%

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02.28 Select Portfolios: Group 7 Information Technology Sector Combo PRO-16 | Communications Equipment Portfolio

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: bold 12pt Arial, Helvetica, sans-serif;">Fund:<br/>Communications Equipment Portfolio</p>

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

The fund seeks capital appreciation.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

Shareholder Fees {- Communications Equipment Portfolio}	02.28 Select Portfolios: Group 7 Information Technology Sector Combo PRO-16 Communications Equipment Portfolio USD ($)
(fees paid directly from your investment)	none

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Annual Operating Expenses {- Communications Equipment Portfolio}	02.28 Select Portfolios: Group 7 Information Technology Sector Combo PRO-16 Communications Equipment Portfolio Communications Equipment Portfolio-Default
Management fee	0.53%
Distribution and/or Service (12b-1) fees	none
Other expenses	0.30%
Total annual operating expenses	0.83%

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Expense Example {- Communications Equipment Portfolio}	02.28 Select Portfolios: Group 7 Information Technology Sector Combo PRO-16 Communications Equipment Portfolio Communications Equipment Portfolio-Default USD ($)
1 year	$ 85
3 years	265
5 years	460
10 years	$ 1,025

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 108% of the average value of its portfolio.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in the development, manufacture, or sale of communications equipment.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Communications Equipment Industry Concentration. The communications equipment industry can be significantly affected by failure to obtain, or delays in obtaining, financing or regulatory approval, intense competition, product compatibility, consumer preferences, corporate capital expenditures, and rapid obsolescence.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

• High Portfolio Turnover. High portfolio turnover (more than 100%) may result in increased transaction costs and potentially higher capital gains or losses. The effects of higher than normal portfolio turnover may adversely affect the fund's performance.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	20.01%	September 30, 2010
Lowest Quarter Return	-25.14%	September 30, 2011
Year-to-Date Return	-19.79%	March 31, 2020

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

Average Annual Total Returns{- Communications Equipment Portfolio} - 02.28 Select Portfolios: Group 7 Information Technology Sector Combo PRO-16 - Communications Equipment Portfolio	Past 1 year	Past 5 years	Past 10 years
Communications Equipment Portfolio-Default | Return Before Taxes	6.09%	5.81%	8.22%
Communications Equipment Portfolio-Default | After Taxes on Distributions	4.85%	4.82%	7.47%
Communications Equipment Portfolio-Default | After Taxes on Distributions and Sales	4.57%	4.42%	6.55%
S&P 500® Index(reflects no deduction for fees, expenses, or taxes)	31.49%	11.70%	13.56%
MSCI North America IMI + ADR Custom Communications Equipment 25/50 Linked Index(reflects no deduction for fees, expenses, or taxes)	6.09%	5.32%	6.46%

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02.28 Select Portfolios: Group 3 Energy Sector Combo PRO-13 | Energy Portfolio

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: bold 12pt Arial, Helvetica, sans-serif;">Fund:<br/>Energy Portfolio</p>

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

The fund seeks capital appreciation.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

Shareholder Fees {- Energy Portfolio}	02.28 Select Portfolios: Group 3 Energy Sector Combo PRO-13 Energy Portfolio USD ($)
(fees paid directly from your investment)	none

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Annual Operating Expenses {- Energy Portfolio}	02.28 Select Portfolios: Group 3 Energy Sector Combo PRO-13 Energy Portfolio Energy Portfolio-Default
Management fee	0.53%
Distribution and/or Service (12b-1) fees	none
Other expenses	0.28%
Total annual operating expenses	0.81%

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Expense Example {- Energy Portfolio}	02.28 Select Portfolios: Group 3 Energy Sector Combo PRO-13 Energy Portfolio Energy Portfolio-Default USD ($)
1 year	$ 83
3 years	259
5 years	450
10 years	$ 1,002

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 79% of the average value of its portfolio.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in the energy field, including the conventional areas of oil, gas, electricity, and coal, and newer sources of energy such as nuclear, geothermal, oil shale, and solar power.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Energy Industry Concentration. The energy industries can be significantly affected by fluctuations in energy prices and supply and demand of energy fuels, energy conservation, the success of exploration projects, and tax and other government regulations.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	24.43%	December 31, 2010
Lowest Quarter Return	-30.22%	December 31, 2018
Year-to-Date Return	-52.25%	March 31, 2020

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

Average Annual Total Returns{- Energy Portfolio} - 02.28 Select Portfolios: Group 3 Energy Sector Combo PRO-13 - Energy Portfolio	Past 1 year	Past 5 years	Past 10 years
Energy Portfolio-Default | Return Before Taxes	9.88%	(3.10%)	0.94%
Energy Portfolio-Default | After Taxes on Distributions	9.40%	(3.42%)	0.22%
Energy Portfolio-Default | After Taxes on Distributions and Sales	6.19%	(2.32%)	0.84%
S&P 500® Index(reflects no deduction for fees, expenses, or taxes)	31.49%	11.70%	13.56%
MSCI U.S. IMI Energy 25-50 Index(reflects no deduction for fees, expenses, or taxes)	9.42%	(3.13%)	2.29%

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02.28 Select Portfolios: Fidelity Advisor Communication Services Fund - AMCIZ PRO-03 | Communication Services Portfolio

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: normal 12pt Arial, Helvetica, sans-serif;"><b>Fund/Class</b>:<br/><b>Communication Services Portfolio</b>/Fidelity Advisor® Communication Services Fund A, M, C, I, Z</p>

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

The fund seeks capital appreciation.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund. In addition to the fees and expenses described below, your broker may also require you to pay brokerage commissions on purchases and sales of certain share classes of the fund.

You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $50,000 in the fund or certain other Fidelity^® funds. More information about these and other discounts is available from your investment professional and in the "Fund Distribution" section beginning on page 28 of the prospectus. Different intermediaries may provide additional waivers or reductions of the sales charge. Please see “Sales Charge Waiver Policies Applied by Certain Intermediaries” in the “Appendix” section of the prospectus.

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(fees paid directly from your investment)</p>

Shareholder Fees {- Communication Services Portfolio} - 02.28 Select Portfolios: Fidelity Advisor Communication Services Fund - AMCIZ PRO-03 - Communication Services Portfolio	Fidelity Advisor Communication Services Fund Class A		Fidelity Advisor Communication Services Fund Class M		Fidelity Advisor Communication Services Fund Class C		Fidelity Advisor Communication Services Fund Class I	Fidelity Advisor Communication Services Fund Class Z
Maximum sales charge (load) on purchases (as a % of offering price)	5.75%		3.50%		none		none	none
Maximum contingent deferred sales charge (as a % of the lesser of original purchase price or redemption proceeds)	none	[1]	none	[1]	1.00%	[2]	none	none

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Annual Operating Expenses {- Communication Services Portfolio} - 02.28 Select Portfolios: Fidelity Advisor Communication Services Fund - AMCIZ PRO-03 - Communication Services Portfolio	Fidelity Advisor Communication Services Fund Class A	Fidelity Advisor Communication Services Fund Class M	Fidelity Advisor Communication Services Fund Class C	Fidelity Advisor Communication Services Fund Class I	Fidelity Advisor Communication Services Fund Class Z
Management fee	0.54%	0.54%	0.54%	0.54%	0.54%
Distribution and/or Service (12b-1) fees	0.25%	0.50%	1.00%	none	none
Other expenses	0.28%	0.31%	0.32%	0.23%	0.11%
Total annual operating expenses	1.07%	1.35%	1.86%	0.77%	0.65%

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated and if you hold your shares:

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Expense Example {- Communication Services Portfolio} - 02.28 Select Portfolios: Fidelity Advisor Communication Services Fund - AMCIZ PRO-03 - Communication Services Portfolio - USD ($)	Fidelity Advisor Communication Services Fund Class A	Fidelity Advisor Communication Services Fund Class M	Fidelity Advisor Communication Services Fund Class C	Fidelity Advisor Communication Services Fund Class I	Fidelity Advisor Communication Services Fund Class Z
1 year	$ 678	$ 483	$ 289	$ 79	$ 66
3 years	896	763	585	246	208
5 years	1,131	1,063	1,006	428	362
10 years	$ 1,806	$ 1,917	$ 2,180	$ 954	$ 810

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Hold Shares</p>

Expense Example, No Redemption {- Communication Services Portfolio} - 02.28 Select Portfolios: Fidelity Advisor Communication Services Fund - AMCIZ PRO-03 - Communication Services Portfolio - USD ($)	Fidelity Advisor Communication Services Fund Class A	Fidelity Advisor Communication Services Fund Class M	Fidelity Advisor Communication Services Fund Class C	Fidelity Advisor Communication Services Fund Class I	Fidelity Advisor Communication Services Fund Class Z
1 Year	$ 678	$ 483	$ 189	$ 79	$ 66
3 Years	896	763	585	246	208
5 Years	1,131	1,063	1,006	428	362
10 Years	$ 1,806	$ 1,917	$ 2,180	$ 954	$ 810

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 73% of the average value of its portfolio.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in the development, production, or distribution of communication services.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Communication Services Concentration. The communication services industries can be significantly affected by government regulation, intense competition, technology changes, general economic conditions, consumer and business confidence and spending, and changes in consumer and business preferences.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the performance of the fund's shares over the past year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Prior to December 1, 2018, the fund was named Multimedia Portfolio, and the fund operated under certain different investment policies and compared its performance to a different additional index. The fund's historical performance may not represent its current investment policies.

Visit institutional.fidelity.com for more recent performance information.

The returns in the bar chart do not reflect any applicable sales charges; if sales charges were reflected, returns would be lower than those shown.

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

During the periods shown in the chart for Class A:	Returns	Quarter ended
Highest Quarter Return	15.44%	March 31, 2019
Lowest Quarter Return	0.78%	September 30, 2019
Year-to-Date Return	-16.80%	March 31, 2020

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

Unlike the returns in the bar chart, the returns in the table reflect the maximum applicable sales charges. After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. After-tax returns for Class A are shown in the table below and after-tax returns for other classes will vary. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

Average Annual Total Returns{- Communication Services Portfolio} - 02.28 Select Portfolios: Fidelity Advisor Communication Services Fund - AMCIZ PRO-03 - Communication Services Portfolio	Past 1 year	Since Inception	[1]	Inception Date
Fidelity Advisor Communication Services Fund Class A				Nov. 28, 2018
Fidelity Advisor Communication Services Fund Class A | Return Before Taxes	24.65%	14.26%
Fidelity Advisor Communication Services Fund Class A | After Taxes on Distributions	15.95%	5.04%		Nov. 28, 2018
Fidelity Advisor Communication Services Fund Class A | After Taxes on Distributions and Sales	19.70%	10.02%		Nov. 28, 2018
Fidelity Advisor Communication Services Fund Class M				Nov. 28, 2018
Fidelity Advisor Communication Services Fund Class M | Return Before Taxes	27.30%	16.46%
Fidelity Advisor Communication Services Fund Class C				Nov. 28, 2018
Fidelity Advisor Communication Services Fund Class C | Return Before Taxes	30.26%	19.73%
Fidelity Advisor Communication Services Fund Class I				Nov. 28, 2018
Fidelity Advisor Communication Services Fund Class I | Return Before Taxes	32.66%	21.03%
Fidelity Advisor Communication Services Fund Class Z				Nov. 28, 2018
Fidelity Advisor Communication Services Fund Class Z | Return Before Taxes	32.82%	21.18%
S&P 500® Index(reflects no deduction for fees, expenses, or taxes)	31.49%	17.98%
MSCI U.S. IMI Communication Services 25-50 (Media Linked) Index(reflects no deduction for fees, expenses, or taxes)	27.94%	15.99%

02.28 Select Portfolios: Fidelity Advisor Communication Services Fund - AMCIZ PRO-03 | Communication Services Portfolio | Fidelity Advisor Communication Services Fund Class A

Class A and Class M purchases of $1 million or more will not be subject to a front-end sales charge. Such Class A and Class M purchases may be subject, upon redemption, to a contingent deferred sales charge (CDSC) of 1.00% or 0.25%, respectively.

02.28 Select Portfolios: Fidelity Advisor Communication Services Fund - AMCIZ PRO-03 | Communication Services Portfolio | Fidelity Advisor Communication Services Fund Class M

Class A and Class M purchases of $1 million or more will not be subject to a front-end sales charge. Such Class A and Class M purchases may be subject, upon redemption, to a contingent deferred sales charge (CDSC) of 1.00% or 0.25%, respectively.

02.28 Select Portfolios: Fidelity Advisor Communication Services Fund - AMCIZ PRO-03 | Communication Services Portfolio | Fidelity Advisor Communication Services Fund Class C

On Class C shares redeemed less than one year after purchase.

[1] Class A and Class M purchases of $1 million or more will not be subject to a front-end sales charge. Such Class A and Class M purchases may be subject, upon redemption, to a contingent deferred sales charge (CDSC) of 1.00% or 0.25%, respectively.

[2] On Class C shares redeemed less than one year after purchase.

[1] From November 28, 2018

XML

Label

Element

Value

Risk/Return:

rr_RiskReturnAbstract

Registrant Name

dei_EntityRegistrantName

FIDELITY SELECT PORTFOLIOS

Prospectus Date

rr_ProspectusDate

Apr. 29, 2020

02.28 Select Portfolios: Group 6 Industrials Sector Combo PRO-10 | Environment and Alternative Energy Portfolio

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: bold 12pt Arial, Helvetica, sans-serif;">Fund:<br/>Environment and Alternative Energy Portfolio</p>

Objective [Heading]

rr_ObjectiveHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks capital appreciation.

Expense [Heading]

rr_ExpenseHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

Shareholder Fees Caption [Text]

rr_ShareholderFeesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

(fees paid directly from your investment)

rr_ShareholderFeeOther

none

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

Portfolio Turnover [Text Block]

rr_PortfolioTurnoverTextBlock

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 49% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

49.00%

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Strategy [Heading]

rr_StrategyHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in business activities related to alternative and renewable energy, energy efficiency, pollution control, water infrastructure, waste and recycling technologies, or other environmental support services.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

Strategy Portfolio Concentration [Text]

rr_StrategyPortfolioConcentration

<font style="FONT-FAMILY: Times New Roman" size="3">Normally investing at least 80% of assets in securities of companies principally engaged in business activities related to alternative and renewable energy, energy efficiency, pollution control, water infrastructure, waste and recycling technologies, or other environmental support services.</font>

Risk [Heading]

rr_RiskHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Environment and Alternative Energy Industry Concentration. The environment and alternative energy industries can be significantly affected by government regulations and subsidies, changing supply and demand for traditional energy sources, and availability of funding for remedial cleanup or development of new technologies, and can be subject to risks associated with hazardous materials.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

Risk Lose Money [Text]

rr_RiskLoseMoney

<font style="FONT-FAMILY: Times New Roman" size="3">You could lose money by investing in the fund.</font>

Risk Nondiversified Status [Text]

rr_RiskNondiversifiedStatus

<font style="FONT-FAMILY: Times New Roman" size="3">In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.</font>

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

<font style="FONT-FAMILY: Times New Roman" size="3">An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</font>

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Prior to July 1, 2010, the fund was named Environmental Portfolio, and the fund operated under certain different investment policies and compared its performance to a different additional index. The fund's historical performance may not represent its current investment policies. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

<font style="FONT-FAMILY: Times New Roman" size="3">The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time.</font>

Performance Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

<font style="FONT-FAMILY: Times New Roman" size="3">www.fidelity.com </font>

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

<font style="FONT-FAMILY: Times New Roman" size="3">Past performance (before and after taxes) is not an indication of future performance.</font>

Bar Chart [Heading]

rr_BarChartHeading

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	15.66%	March 31, 2019
Lowest Quarter Return	-25.92%	September 30, 2011
Year-to-Date Return	-26.22%	March 31, 2020

Performance Table Heading

rr_PerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

<font style="FONT-FAMILY: Times New Roman" size="3">After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes.</font>

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

<font style="FONT-FAMILY: Times New Roman" size="3">The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan).</font>

Performance Table Explanation after Tax Higher

rr_PerformanceTableExplanationAfterTaxHigher

<font style="FONT-FAMILY: Times New Roman" size="3">Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.</font>

Performance Table Narrative

rr_PerformanceTableNarrativeTextBlock

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

02.28 Select Portfolios: Group 6 Industrials Sector Combo PRO-10 | Environment and Alternative Energy Portfolio | Environment and Alternative Energy Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Management fee

rr_ManagementFeesOverAssets

0.54%

Distribution and/or Service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

none

Other expenses

rr_OtherExpensesOverAssets

0.31%

Total annual operating expenses

rr_ExpensesOverAssets

0.85%

1 year

rr_ExpenseExampleYear01

$ 87

3 years

rr_ExpenseExampleYear03

271

5 years

rr_ExpenseExampleYear05

471

10 years

rr_ExpenseExampleYear10

$ 1,049

2010

rr_AnnualReturn2010

14.93%

2011

rr_AnnualReturn2011

(14.30%)

2012

rr_AnnualReturn2012

14.15%

2013

rr_AnnualReturn2013

34.99%

2014

rr_AnnualReturn2014

1.86%

2015

rr_AnnualReturn2015

(4.59%)

2016

rr_AnnualReturn2016

20.72%

2017

rr_AnnualReturn2017

25.25%

2018

rr_AnnualReturn2018

(13.43%)

2019

rr_AnnualReturn2019

26.83%

Year to Date Return, Label

rr_YearToDateReturnLabel

Year-to-Date Return

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Mar. 31, 2020

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

(26.22%)

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Highest Quarter Return

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Mar. 31, 2019

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

15.66%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Lowest Quarter Return

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Sep. 30, 2011

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(25.92%)

02.28 Select Portfolios: Group 6 Industrials Sector Combo PRO-10 | Environment and Alternative Energy Portfolio | Return Before Taxes | Environment and Alternative Energy Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Environment and Alternative Energy Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return Before Taxes</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

26.83%

Past 5 years

rr_AverageAnnualReturnYear05

9.64%

Past 10 years

rr_AverageAnnualReturnYear10

9.37%

02.28 Select Portfolios: Group 6 Industrials Sector Combo PRO-10 | Environment and Alternative Energy Portfolio | After Taxes on Distributions | Environment and Alternative Energy Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Environment and Alternative Energy Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

26.17%

Past 5 years

rr_AverageAnnualReturnYear05

8.62%

Past 10 years

rr_AverageAnnualReturnYear10

8.48%

02.28 Select Portfolios: Group 6 Industrials Sector Combo PRO-10 | Environment and Alternative Energy Portfolio | After Taxes on Distributions and Sales | Environment and Alternative Energy Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Environment and Alternative Energy Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions and Sale of Fund Shares</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

16.33%

Past 5 years

rr_AverageAnnualReturnYear05

7.44%

Past 10 years

rr_AverageAnnualReturnYear10

7.50%

02.28 Select Portfolios: Group 6 Industrials Sector Combo PRO-10 | Environment and Alternative Energy Portfolio | S&P 500® Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

31.49%

Past 5 years

rr_AverageAnnualReturnYear05

11.70%

Past 10 years

rr_AverageAnnualReturnYear10

13.56%

02.28 Select Portfolios: Group 6 Industrials Sector Combo PRO-10 | Environment and Alternative Energy Portfolio | FTSE® Environmental Opportunities & Alternative Energy Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

33.55%

Past 5 years

rr_AverageAnnualReturnYear05

11.50%

Past 10 years

rr_AverageAnnualReturnYear10

11.88%

XML

Total

02.28 Select Portfolios: Group 6 Industrials Sector Combo PRO-10 | Defense and Aerospace Portfolio

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: bold 12pt Arial, Helvetica, sans-serif;">Fund:<br/>Defense and Aerospace Portfolio</p>

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

The fund seeks capital appreciation.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

Shareholder Fees {- Defense and Aerospace Portfolio}	02.28 Select Portfolios: Group 6 Industrials Sector Combo PRO-10 Defense and Aerospace Portfolio USD ($)
(fees paid directly from your investment)	none

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Annual Operating Expenses {- Defense and Aerospace Portfolio}	02.28 Select Portfolios: Group 6 Industrials Sector Combo PRO-10 Defense and Aerospace Portfolio Defense and Aerospace Portfolio-Default
Management fee	0.54%
Distribution and/or Service (12b-1) fees	none
Other expenses	0.21%
Total annual operating expenses	0.75%

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Expense Example {- Defense and Aerospace Portfolio}	02.28 Select Portfolios: Group 6 Industrials Sector Combo PRO-10 Defense and Aerospace Portfolio Defense and Aerospace Portfolio-Default USD ($)
1 year	$ 77
3 years	240
5 years	417
10 years	$ 930

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 40% of the average value of its portfolio.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in the research, manufacture, or sale of products or services related to the defense or aerospace industries.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Defense and Aerospace Industry Concentration. The defense and aerospace industry can be significantly affected by government defense and aerospace regulation and spending policies.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	17.20%	March 31, 2019
Lowest Quarter Return	-19.70%	December 31, 2018
Year-to-Date Return	-32.77%	March 31, 2020

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

Average Annual Total Returns{- Defense and Aerospace Portfolio} - 02.28 Select Portfolios: Group 6 Industrials Sector Combo PRO-10 - Defense and Aerospace Portfolio	Past 1 year	Past 5 years	Past 10 years
Defense and Aerospace Portfolio-Default | Return Before Taxes	33.74%	15.37%	16.56%
Defense and Aerospace Portfolio-Default | After Taxes on Distributions	32.93%	13.88%	15.41%
Defense and Aerospace Portfolio-Default | After Taxes on Distributions and Sales	20.56%	12.04%	13.77%
S&P 500® Index(reflects no deduction for fees, expenses, or taxes)	31.49%	11.70%	13.56%
MSCI U.S. IMI Aerospace & Defense 25-50 Index(reflects no deduction for fees, expenses, or taxes)	34.05%	17.53%	18.79%

XML

Label

Element

Value

Risk/Return:

rr_RiskReturnAbstract

Registrant Name

dei_EntityRegistrantName

FIDELITY SELECT PORTFOLIOS

Prospectus Date

rr_ProspectusDate

Apr. 29, 2020

02.28 Select Portfolios: Group 1 Consumer Discretionary Sector Combo PRO-16 | Communication Services Portfolio

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: normal 12pt Arial, Helvetica, sans-serif;"><b>Fund/Class</b>:<br/><b>Communication Services Portfolio</b>/Communication Services Portfolio</p>

Objective [Heading]

rr_ObjectiveHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks capital appreciation.

Expense [Heading]

rr_ExpenseHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

Shareholder Fees Caption [Text]

rr_ShareholderFeesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

(fees paid directly from your investment)

rr_ShareholderFeeOther

none

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

Portfolio Turnover [Text Block]

rr_PortfolioTurnoverTextBlock

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 73% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

73.00%

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Strategy [Heading]

rr_StrategyHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in the development, production, or distribution of communication services.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

Strategy Portfolio Concentration [Text]

rr_StrategyPortfolioConcentration

<font style="FONT-FAMILY: Times New Roman" size="3">Normally investing at least 80% of assets in securities of companies principally engaged in the development, production, or distribution of communication services.</font>

Risk [Heading]

rr_RiskHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Communication Services Concentration. The communication services industries can be significantly affected by government regulation, intense competition, technology changes, general economic conditions, consumer and business confidence and spending, and changes in consumer and business preferences.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

Risk Lose Money [Text]

rr_RiskLoseMoney

<font style="FONT-FAMILY: Times New Roman" size="3">You could lose money by investing in the fund.</font>

Risk Nondiversified Status [Text]

rr_RiskNondiversifiedStatus

<font style="FONT-FAMILY: Times New Roman" size="3">In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.</font>

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

<font style="FONT-FAMILY: Times New Roman" size="3">An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</font>

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Prior to December 1, 2018, the fund was named Multimedia Portfolio, and the fund operated under certain different investment policies and compared its performance to a different additional index. The fund's historical performance may not represent its current investment policies. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

<font style="FONT-FAMILY: Times New Roman" size="3">The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time.</font>

Performance Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

<font style="FONT-FAMILY: Times New Roman" size="3">www.fidelity.com </font>

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

<font style="FONT-FAMILY: Times New Roman" size="3">Past performance (before and after taxes) is not an indication of future performance.</font>

Bar Chart [Heading]

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<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	16.03%	March 31, 2012
Lowest Quarter Return	-20.43%	September 30, 2011
Year-to-Date Return	-16.73%	March 31, 2020

Performance Table Heading

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<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

<font style="FONT-FAMILY: Times New Roman" size="3">After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes.</font>

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

<font style="FONT-FAMILY: Times New Roman" size="3">The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan).</font>

Performance Table Explanation after Tax Higher

rr_PerformanceTableExplanationAfterTaxHigher

<font style="FONT-FAMILY: Times New Roman" size="3">Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.</font>

Performance Table Narrative

rr_PerformanceTableNarrativeTextBlock

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

02.28 Select Portfolios: Group 1 Consumer Discretionary Sector Combo PRO-16 | Communication Services Portfolio | Communication Services Portfolio

Risk/Return:

rr_RiskReturnAbstract

Management fee

rr_ManagementFeesOverAssets

0.54%

Distribution and/or Service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

none

Other expenses

rr_OtherExpensesOverAssets

0.24%

Total annual operating expenses

rr_ExpensesOverAssets

0.78%

1 year

rr_ExpenseExampleYear01

$ 80

3 years

rr_ExpenseExampleYear03

249

5 years

rr_ExpenseExampleYear05

433

10 years

rr_ExpenseExampleYear10

$ 966

2010

rr_AnnualReturn2010

25.80%

2011

rr_AnnualReturn2011

1.83%

2012

rr_AnnualReturn2012

34.22%

2013

rr_AnnualReturn2013

45.65%

2014

rr_AnnualReturn2014

8.29%

2015

rr_AnnualReturn2015

(2.17%)

2016

rr_AnnualReturn2016

9.50%

2017

rr_AnnualReturn2017

12.59%

2018

rr_AnnualReturn2018

(3.27%)

2019

rr_AnnualReturn2019

32.62%

Year to Date Return, Label

rr_YearToDateReturnLabel

Year-to-Date Return

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Mar. 31, 2020

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

(16.73%)

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Highest Quarter Return

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Mar. 31, 2012

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

16.03%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Lowest Quarter Return

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Sep. 30, 2011

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(20.43%)

02.28 Select Portfolios: Group 1 Consumer Discretionary Sector Combo PRO-16 | Communication Services Portfolio | Return Before Taxes | Communication Services Portfolio

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Communication Services Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return Before Taxes</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

32.62%

Past 5 years

rr_AverageAnnualReturnYear05

9.12%

Past 10 years

rr_AverageAnnualReturnYear10

15.42%

02.28 Select Portfolios: Group 1 Consumer Discretionary Sector Combo PRO-16 | Communication Services Portfolio | After Taxes on Distributions | Communication Services Portfolio

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Communication Services Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

23.35%

Past 5 years

rr_AverageAnnualReturnYear05

5.87%

Past 10 years

rr_AverageAnnualReturnYear10

13.32%

02.28 Select Portfolios: Group 1 Consumer Discretionary Sector Combo PRO-16 | Communication Services Portfolio | After Taxes on Distributions and Sales | Communication Services Portfolio

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Communication Services Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions and Sale of Fund Shares</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

24.71%

Past 5 years

rr_AverageAnnualReturnYear05

6.72%

Past 10 years

rr_AverageAnnualReturnYear10

12.69%

02.28 Select Portfolios: Group 1 Consumer Discretionary Sector Combo PRO-16 | Communication Services Portfolio | S&P 500® Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

31.49%

Past 5 years

rr_AverageAnnualReturnYear05

11.70%

Past 10 years

rr_AverageAnnualReturnYear10

13.56%

02.28 Select Portfolios: Group 1 Consumer Discretionary Sector Combo PRO-16 | Communication Services Portfolio | MSCI U.S. IMI Communication Services 25-50 (Media Linked) Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

27.94%

Past 5 years

rr_AverageAnnualReturnYear05

7.41%

Past 10 years

rr_AverageAnnualReturnYear10

16.02%

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Total

02.28 Select Portfolios: Fidelity Advisor Telecommunications Fund AMCIZ PRO-11 | Telecommunications Portfolio

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: normal 12pt Arial, Helvetica, sans-serif;"><b>Fund/Class</b>:<br/><b>Telecommunications Portfolio</b>/Fidelity Advisor® Telecommunications Fund A, M, C, I, Z</p>

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

The fund seeks capital appreciation.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund. In addition to the fees and expenses described below, your broker may also require you to pay brokerage commissions on purchases and sales of certain share classes of the fund.

You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $50,000 in the fund or certain other Fidelity^® funds. More information about these and other discounts is available from your investment professional and in the "Fund Distribution" section beginning on page 27 of the prospectus. Different intermediaries may provide additional waivers or reductions of the sales charge. Please see “Sales Charge Waiver Policies Applied by Certain Intermediaries” in the “Appendix” section of the prospectus.

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(fees paid directly from your investment)</p>

Shareholder Fees {- Telecommunications Portfolio} - 02.28 Select Portfolios: Fidelity Advisor Telecommunications Fund AMCIZ PRO-11 - Telecommunications Portfolio	Fidelity Advisor Telecommunications Fund: Class A		Fidelity Advisor Telecommunications Fund: Class M		Fidelity Advisor Telecommunications Fund: Class C		Fidelity Advisor Telecommunications Fund: Class I	Fidelity Advisor Telecommunications Fund: Class Z
Maximum sales charge (load) on purchases (as a % of offering price)	5.75%		3.50%		none		none	none
Maximum contingent deferred sales charge (as a % of the lesser of original purchase price or redemption proceeds)	none	[1]	none	[1]	1.00%	[2]	none	none

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Annual Operating Expenses {- Telecommunications Portfolio} - 02.28 Select Portfolios: Fidelity Advisor Telecommunications Fund AMCIZ PRO-11 - Telecommunications Portfolio	Fidelity Advisor Telecommunications Fund: Class A	Fidelity Advisor Telecommunications Fund: Class M	Fidelity Advisor Telecommunications Fund: Class C	Fidelity Advisor Telecommunications Fund: Class I	Fidelity Advisor Telecommunications Fund: Class Z
Management fee	0.54%	0.54%	0.54%	0.54%	0.54%
Distribution and/or Service (12b-1) fees	0.25%	0.50%	1.00%	none	none
Other expenses	0.39%	0.42%	0.34%	0.34%	0.14%
Total annual operating expenses	1.18%	1.46%	1.88%	0.88%	0.68%

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated and if you hold your shares:

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Expense Example {- Telecommunications Portfolio} - 02.28 Select Portfolios: Fidelity Advisor Telecommunications Fund AMCIZ PRO-11 - Telecommunications Portfolio - USD ($)	Fidelity Advisor Telecommunications Fund: Class A	Fidelity Advisor Telecommunications Fund: Class M	Fidelity Advisor Telecommunications Fund: Class C	Fidelity Advisor Telecommunications Fund: Class I	Fidelity Advisor Telecommunications Fund: Class Z
1 year	$ 688	$ 493	$ 291	$ 90	$ 69
3 years	928	796	591	281	218
5 years	1,187	1,120	1,016	488	379
10 years	$ 1,924	$ 2,035	$ 2,201	$ 1,084	$ 847

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Hold Shares</p>

Expense Example, No Redemption {- Telecommunications Portfolio} - 02.28 Select Portfolios: Fidelity Advisor Telecommunications Fund AMCIZ PRO-11 - Telecommunications Portfolio - USD ($)	Fidelity Advisor Telecommunications Fund: Class A	Fidelity Advisor Telecommunications Fund: Class M	Fidelity Advisor Telecommunications Fund: Class C	Fidelity Advisor Telecommunications Fund: Class I	Fidelity Advisor Telecommunications Fund: Class Z
1 Year	$ 688	$ 493	$ 191	$ 90	$ 69
3 Years	928	796	591	281	218
5 Years	1,187	1,120	1,016	488	379
10 Years	$ 1,924	$ 2,035	$ 2,201	$ 1,084	$ 847

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 58% of the average value of its portfolio.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in the development, production, or distribution of telecommunications services.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Telecom Services Industry Concentration. The telecom services industry is subject to government regulation and can be significantly affected by intense competition and technology changes.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit institutional.fidelity.com for more recent performance information.

The returns in the bar chart do not reflect any applicable sales charges; if sales charges were reflected, returns would be lower than those shown.

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

During the periods shown in the chart for Class A:	Returns	Quarter ended
Highest Quarter Return	17.53%	September 30, 2010
Lowest Quarter Return	-17.05%	September 30, 2011
Year-to-Date Return	-8.20%	March 31, 2020

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

Unlike the returns in the bar chart, the returns in the table reflect the maximum applicable sales charges. After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. After-tax returns for Class A are shown in the table below and after-tax returns for other classes will vary. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

Average Annual Total Returns{- Telecommunications Portfolio} - 02.28 Select Portfolios: Fidelity Advisor Telecommunications Fund AMCIZ PRO-11 - Telecommunications Portfolio	Past 1 year	Past 5 years	Past 10 years	Since Inception	[1]	Inception Date
Fidelity Advisor Telecommunications Fund: Class A | Return Before Taxes	13.07%	5.57%	8.13%
Fidelity Advisor Telecommunications Fund: Class A | After Taxes on Distributions	12.28%	3.95%	7.09%
Fidelity Advisor Telecommunications Fund: Class A | After Taxes on Distributions and Sales	8.29%	4.13%	6.49%
Fidelity Advisor Telecommunications Fund: Class M | Return Before Taxes	15.44%	5.73%	8.05%
Fidelity Advisor Telecommunications Fund: Class C | Return Before Taxes	18.14%	6.06%	7.99%
Fidelity Advisor Telecommunications Fund: Class I | Return Before Taxes	20.33%	7.17%	9.11%
Fidelity Advisor Telecommunications Fund: Class Z | Return Before Taxes	20.58%			4.31%		Oct. 02, 2018
S&P 500® Index(reflects no deduction for fees, expenses, or taxes)	31.49%	11.70%	13.56%
MSCI U.S. IM Telecommunication Services 25-50 Index(reflects no deduction for fees, expenses, or taxes)	12.64%	4.11%	7.99%

02.28 Select Portfolios: Fidelity Advisor Telecommunications Fund AMCIZ PRO-11 | Telecommunications Portfolio | Fidelity Advisor Telecommunications Fund: Class A

Class A and Class M purchases of $1 million or more will not be subject to a front-end sales charge. Such Class A and Class M purchases may be subject, upon redemption, to a contingent deferred sales charge (CDSC) of 1.00% or 0.25%, respectively.

02.28 Select Portfolios: Fidelity Advisor Telecommunications Fund AMCIZ PRO-11 | Telecommunications Portfolio | Fidelity Advisor Telecommunications Fund: Class M

Class A and Class M purchases of $1 million or more will not be subject to a front-end sales charge. Such Class A and Class M purchases may be subject, upon redemption, to a contingent deferred sales charge (CDSC) of 1.00% or 0.25%, respectively.

02.28 Select Portfolios: Fidelity Advisor Telecommunications Fund AMCIZ PRO-11 | Telecommunications Portfolio | Fidelity Advisor Telecommunications Fund: Class C

On Class C shares redeemed less than one year after purchase.

[1] Class A and Class M purchases of $1 million or more will not be subject to a front-end sales charge. Such Class A and Class M purchases may be subject, upon redemption, to a contingent deferred sales charge (CDSC) of 1.00% or 0.25%, respectively.

[2] On Class C shares redeemed less than one year after purchase.

[1] Since inception October 2, 2018.

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02.28 Select Portfolios: Group 8 Materials Sector Retail Combo PRO-15 | Chemicals Portfolio

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: bold 12pt Arial, Helvetica, sans-serif;">Fund:<br/>Chemicals Portfolio</p>

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

The fund seeks capital appreciation.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

Shareholder Fees {- Chemicals Portfolio}	02.28 Select Portfolios: Group 8 Materials Sector Retail Combo PRO-15 Chemicals Portfolio USD ($)
(fees paid directly from your investment)	none

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Annual Operating Expenses {- Chemicals Portfolio}	02.28 Select Portfolios: Group 8 Materials Sector Retail Combo PRO-15 Chemicals Portfolio Chemicals Portfolio-Default
Management fee	0.53%
Distribution and/or Service (12b-1) fees	none
Other expenses	0.25%
Total annual operating expenses	0.78%

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Expense Example {- Chemicals Portfolio}	02.28 Select Portfolios: Group 8 Materials Sector Retail Combo PRO-15 Chemicals Portfolio Chemicals Portfolio-Default USD ($)
1 year	$ 80
3 years	249
5 years	433
10 years	$ 966

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 77% of the average value of its portfolio.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in the research, development, manufacture, or marketing of products or services related to the chemical process industries.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Chemicals Industry Concentration. The chemicals industry can be significantly affected by intense competition, product obsolescence, raw materials prices, and government regulation, and can be subject to risks associated with the production, handling, and disposal of hazardous components.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	22.72%	September 30, 2010
Lowest Quarter Return	-24.12%	September 30, 2011
Year-to-Date Return	-29.08%	March 31, 2020

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

Average Annual Total Returns{- Chemicals Portfolio} - 02.28 Select Portfolios: Group 8 Materials Sector Retail Combo PRO-15 - Chemicals Portfolio	Past 1 year	Past 5 years	Past 10 years
Chemicals Portfolio-Default | Return Before Taxes	8.24%	4.44%	11.14%
Chemicals Portfolio-Default | After Taxes on Distributions	6.59%	2.39%	9.62%
Chemicals Portfolio-Default | After Taxes on Distributions and Sales	6.13%	3.25%	9.03%
S&P 500® Index(reflects no deduction for fees, expenses, or taxes)	31.49%	11.70%	13.56%
MSCI U.S. IMI Chemicals 25-50 Index(reflects no deduction for fees, expenses, or taxes)	19.69%	7.20%	12.46%

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02.28 Select Portfolios: Group 3 Energy Sector Combo PRO-13 | Natural Gas Portfolio

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: bold 12pt Arial, Helvetica, sans-serif;">Fund:<br/>Natural Gas Portfolio</p>

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

The fund seeks capital appreciation.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

Shareholder Fees {- Natural Gas Portfolio}	02.28 Select Portfolios: Group 3 Energy Sector Combo PRO-13 Natural Gas Portfolio USD ($)
(fees paid directly from your investment)	none

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Annual Operating Expenses {- Natural Gas Portfolio}	02.28 Select Portfolios: Group 3 Energy Sector Combo PRO-13 Natural Gas Portfolio Natural Gas Portfolio-Default
Management fee	0.53%
Distribution and/or Service (12b-1) fees	none
Other expenses	0.40%
Total annual operating expenses	0.93%

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Expense Example {- Natural Gas Portfolio}	02.28 Select Portfolios: Group 3 Energy Sector Combo PRO-13 Natural Gas Portfolio Natural Gas Portfolio-Default USD ($)
1 year	$ 95
3 years	296
5 years	515
10 years	$ 1,143

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 87% of the average value of its portfolio.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in the production, transmission, and distribution of natural gas, and involved in the exploration of potential natural gas sources, as well as those companies that provide services and equipment to natural gas producers, refineries, cogeneration facilities, converters, and distributors.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Natural Gas Industry Concentration. The natural gas industry is subject to changes in price and supply of energy sources and can be significantly affected by events relating to international politics, energy conservation, the success of energy source exploration projects, and tax and other government regulations.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	18.16%	June 30, 2016
Lowest Quarter Return	-30.78%	December 31, 2018
Year-to-Date Return	-55.51%	March 31, 2020

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

Average Annual Total Returns{- Natural Gas Portfolio} - 02.28 Select Portfolios: Group 3 Energy Sector Combo PRO-13 - Natural Gas Portfolio	Past 1 year	Past 5 years	Past 10 years
Natural Gas Portfolio-Default | Return Before Taxes	3.58%	(9.36%)	(3.99%)
Natural Gas Portfolio-Default | After Taxes on Distributions	3.32%	(9.74%)	(4.30%)
Natural Gas Portfolio-Default | After Taxes on Distributions and Sales	2.30%	(6.76%)	(2.80%)
S&P 500® Index(reflects no deduction for fees, expenses, or taxes)	31.49%	11.70%	13.56%
FactSet Natural Gas Linked Index(reflects no deduction for fees, expenses, or taxes)	11.75%	(5.48%)	0.22%

XML

Label

Element

Value

Risk/Return:

rr_RiskReturnAbstract

Registrant Name

dei_EntityRegistrantName

FIDELITY SELECT PORTFOLIOS

Prospectus Date

rr_ProspectusDate

Apr. 29, 2020

02.28 Select Portfolios: Group 9 Telecommunications Services Sector Retail Combo PRO-13 | Wireless Portfolio

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: bold 12pt Arial, Helvetica, sans-serif;">Fund:<br/>Wireless Portfolio</p>

Objective [Heading]

rr_ObjectiveHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks capital appreciation.

Expense [Heading]

rr_ExpenseHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

Shareholder Fees Caption [Text]

rr_ShareholderFeesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

(fees paid directly from your investment)

rr_ShareholderFeeOther

none

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

Portfolio Turnover [Text Block]

rr_PortfolioTurnoverTextBlock

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 78% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

78.00%

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Strategy [Heading]

rr_StrategyHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in activities relating to wireless communications services or products.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

Strategy Portfolio Concentration [Text]

rr_StrategyPortfolioConcentration

<font style="FONT-FAMILY: Times New Roman" size="3">Normally investing at least 80% of assets in securities of companies principally engaged in activities relating to wireless communications services or products.</font>

Risk [Heading]

rr_RiskHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Wireless Industry Concentration. The wireless industry can be significantly affected by failure or delays in obtaining financing or regulatory approval, intense competition, product incompatibility, changing consumer preferences, rapid obsolescence, significant capital expenditures, and heavy debt burdens.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

Risk Lose Money [Text]

rr_RiskLoseMoney

<font style="FONT-FAMILY: Times New Roman" size="3">You could lose money by investing in the fund.</font>

Risk Nondiversified Status [Text]

rr_RiskNondiversifiedStatus

<font style="FONT-FAMILY: Times New Roman" size="3">In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.</font>

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

<font style="FONT-FAMILY: Times New Roman" size="3">An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</font>

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

<font style="FONT-FAMILY: Times New Roman" size="3">The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time.</font>

Performance Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

<font style="FONT-FAMILY: Times New Roman" size="3">www.fidelity.com </font>

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

<font style="FONT-FAMILY: Times New Roman" size="3">Past performance (before and after taxes) is not an indication of future performance.</font>

Bar Chart [Heading]

rr_BarChartHeading

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	15.88%	September 30, 2010
Lowest Quarter Return	-12.62%	December 31, 2018
Year-to-Date Return	-13.02%	March 31, 2020

Performance Table Heading

rr_PerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

<font style="FONT-FAMILY: Times New Roman" size="3">After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes.</font>

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

<font style="FONT-FAMILY: Times New Roman" size="3">The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan).</font>

Performance Table Explanation after Tax Higher

rr_PerformanceTableExplanationAfterTaxHigher

<font style="FONT-FAMILY: Times New Roman" size="3">Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.</font>

Performance Table Narrative

rr_PerformanceTableNarrativeTextBlock

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

02.28 Select Portfolios: Group 9 Telecommunications Services Sector Retail Combo PRO-13 | Wireless Portfolio | Wireless Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Management fee

rr_ManagementFeesOverAssets

0.54%

Distribution and/or Service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

none

Other expenses

rr_OtherExpensesOverAssets

0.27%

Total annual operating expenses

rr_ExpensesOverAssets

0.81%

1 year

rr_ExpenseExampleYear01

$ 83

3 years

rr_ExpenseExampleYear03

259

5 years

rr_ExpenseExampleYear05

450

10 years

rr_ExpenseExampleYear10

$ 1,002

2010

rr_AnnualReturn2010

15.17%

2011

rr_AnnualReturn2011

(0.96%)

2012

rr_AnnualReturn2012

16.30%

2013

rr_AnnualReturn2013

28.26%

2014

rr_AnnualReturn2014

2.98%

2015

rr_AnnualReturn2015

(3.09%)

2016

rr_AnnualReturn2016

10.07%

2017

rr_AnnualReturn2017

25.02%

2018

rr_AnnualReturn2018

(6.21%)

2019

rr_AnnualReturn2019

40.14%

Year to Date Return, Label

rr_YearToDateReturnLabel

Year-to-Date Return

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Mar. 31, 2020

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

(13.02%)

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Highest Quarter Return

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Sep. 30, 2010

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

15.88%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Lowest Quarter Return

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Dec. 31, 2018

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(12.62%)

02.28 Select Portfolios: Group 9 Telecommunications Services Sector Retail Combo PRO-13 | Wireless Portfolio | Return Before Taxes | Wireless Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Wireless Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return Before Taxes</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

40.14%

Past 5 years

rr_AverageAnnualReturnYear05

11.88%

Past 10 years

rr_AverageAnnualReturnYear10

11.87%

02.28 Select Portfolios: Group 9 Telecommunications Services Sector Retail Combo PRO-13 | Wireless Portfolio | After Taxes on Distributions | Wireless Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Wireless Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

39.16%

Past 5 years

rr_AverageAnnualReturnYear05

10.01%

Past 10 years

rr_AverageAnnualReturnYear10

10.29%

02.28 Select Portfolios: Group 9 Telecommunications Services Sector Retail Combo PRO-13 | Wireless Portfolio | After Taxes on Distributions and Sales | Wireless Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Wireless Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions and Sale of Fund Shares</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

24.31%

Past 5 years

rr_AverageAnnualReturnYear05

8.98%

Past 10 years

rr_AverageAnnualReturnYear10

9.39%

02.28 Select Portfolios: Group 9 Telecommunications Services Sector Retail Combo PRO-13 | Wireless Portfolio | S&P 500® Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

31.49%

Past 5 years

rr_AverageAnnualReturnYear05

11.70%

Past 10 years

rr_AverageAnnualReturnYear10

13.56%

02.28 Select Portfolios: Group 9 Telecommunications Services Sector Retail Combo PRO-13 | Wireless Portfolio | Fidelity Wireless Index℠(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

30.89%

Past 5 years

rr_AverageAnnualReturnYear05

9.08%

Past 10 years

rr_AverageAnnualReturnYear10

8.96%

XML

Label

Element

Value

Risk/Return:

rr_RiskReturnAbstract

Registrant Name

dei_EntityRegistrantName

FIDELITY SELECT PORTFOLIOS

Prospectus Date

rr_ProspectusDate

Apr. 29, 2020

02.28 Select Portfolios: Group 8 Materials Sector Retail Combo PRO-15 | Gold Portfolio

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: normal 12pt Arial, Helvetica, sans-serif;"><b>Fund/Class</b>:<br/><b>Gold Portfolio</b>/Gold Portfolio</p>

Objective [Heading]

rr_ObjectiveHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks capital appreciation.

Expense [Heading]

rr_ExpenseHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

Shareholder Fees Caption [Text]

rr_ShareholderFeesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

(fees paid directly from your investment)

rr_ShareholderFeeOther

none

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

Portfolio Turnover [Text Block]

rr_PortfolioTurnoverTextBlock

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 56% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

56.00%

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Strategy [Heading]

rr_StrategyHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

• Normally investing primarily in common stocks and in certain precious metals.

• Investing primarily in companies engaged in exploration, mining, processing, or dealing in gold, or to a lesser degree, in silver, platinum, diamonds, or other precious metals and minerals.

• Normally investing at least 80% of assets in securities of companies principally engaged in gold-related activities, and in gold bullion or coins.

• Investing up to 25% of assets in gold and other precious metals through a wholly-owned subsidiary organized under the laws of the Cayman Islands.

• Potentially investing in other precious metals, instruments whose value is linked to the price of precious metals, and securities of companies that manufacture and distribute precious metal and minerals products (such as jewelry, watches, and metal foil and leaf) and companies that invest in other companies engaged in gold and other precious metal and mineral-related activities.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

Strategy Portfolio Concentration [Text]

rr_StrategyPortfolioConcentration

<font style="FONT-FAMILY: Times New Roman" size="3">Normally investing at least 80% of assets in securities of companies principally engaged in gold-related activities, and in gold bullion or coins.</font>

Risk [Heading]

rr_RiskHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets, particularly emerging markets, can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market. Emerging markets can be subject to greater social, economic, regulatory, and political uncertainties and can be extremely volatile. Foreign exchange rates also can be extremely volatile.

• Geographic Concentration in Canada. Because an underlying fund concentrates its investments in Canada, the underlying fund's performance is expected to be closely tied to social, political, and economic conditions within Canada and to be more volatile than the performance of more geographically diversified funds. In addition, because the underlying fund may invest a significant percentage of assets in certain industries, the underlying fund's performance could be affected to the extent that the particular industry or industries in which the fund invests are sensitive to adverse social, political, economic, currency, or regulatory developments.

• Gold Industry Concentration. The gold industry can be significantly affected by international monetary and political developments such as currency devaluations or revaluations, central bank movements, economic and social conditions within a country, trade imbalances, or trade or currency restrictions between countries, as well as supply and demand for gold and operational costs associated with mining.

• Subsidiary Risk. Investment in Fidelity Select Gold Cayman Ltd., an unregistered subsidiary, is not subject to the investor protections of the Investment Company Act of 1940 (1940 Act) and is subject to the risks associated with the gold industry. Changes in tax and other laws could negatively affect investments in the subsidiary.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the 1940 Act, which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

Risk Lose Money [Text]

rr_RiskLoseMoney

<font style="FONT-FAMILY: Times New Roman" size="3">You could lose money by investing in the fund.</font>

Risk Nondiversified Status [Text]

rr_RiskNondiversifiedStatus

<font style="FONT-FAMILY: Times New Roman" size="3">In addition, the fund is classified as non-diversified under the 1940 Act, which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.</font>

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

<font style="FONT-FAMILY: Times New Roman" size="3">An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</font>

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

<font style="FONT-FAMILY: Times New Roman" size="3">The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time.</font>

Performance Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

<font style="FONT-FAMILY: Times New Roman" size="3">www.fidelity.com </font>

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

<font style="FONT-FAMILY: Times New Roman" size="3">Past performance (before and after taxes) is not an indication of future performance.</font>

Bar Chart [Heading]

rr_BarChartHeading

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	41.04%	March 31, 2016
Lowest Quarter Return	-37.37%	June 30, 2013
Year-to-Date Return	-19.07%	March 31, 2020

Performance Table Heading

rr_PerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

<font style="FONT-FAMILY: Times New Roman" size="3">After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes.</font>

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

<font style="FONT-FAMILY: Times New Roman" size="3">The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan).</font>

Performance Table Explanation after Tax Higher

rr_PerformanceTableExplanationAfterTaxHigher

<font style="FONT-FAMILY: Times New Roman" size="3">Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.</font>

Performance Table Narrative

rr_PerformanceTableNarrativeTextBlock

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

02.28 Select Portfolios: Group 8 Materials Sector Retail Combo PRO-15 | Gold Portfolio | Gold Portfolio

Risk/Return:

rr_RiskReturnAbstract

Management fee

rr_ManagementFeesOverAssets

0.54%

Distribution and/or Service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

none

Other expenses

rr_OtherExpensesOverAssets

0.25%

Total annual operating expenses

rr_ExpensesOverAssets

0.79%

1 year

rr_ExpenseExampleYear01

$ 81

3 years

rr_ExpenseExampleYear03

252

5 years

rr_ExpenseExampleYear05

439

10 years

rr_ExpenseExampleYear10

$ 978

2010

rr_AnnualReturn2010

35.25%

2011

rr_AnnualReturn2011

(16.34%)

2012

rr_AnnualReturn2012

(12.43%)

2013

rr_AnnualReturn2013

(51.41%)

2014

rr_AnnualReturn2014

(8.51%)

2015

rr_AnnualReturn2015

(17.88%)

2016

rr_AnnualReturn2016

47.28%

2017

rr_AnnualReturn2017

8.63%

2018

rr_AnnualReturn2018

(13.00%)

2019

rr_AnnualReturn2019

35.50%

Year to Date Return, Label

rr_YearToDateReturnLabel

Year-to-Date Return

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Mar. 31, 2020

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

(19.07%)

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Highest Quarter Return

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Mar. 31, 2016

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

41.04%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Lowest Quarter Return

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Jun. 30, 2013

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(37.37%)

02.28 Select Portfolios: Group 8 Materials Sector Retail Combo PRO-15 | Gold Portfolio | Return Before Taxes | Gold Portfolio

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Gold Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return Before Taxes</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

35.50%

Past 5 years

rr_AverageAnnualReturnYear05

9.14%

Past 10 years

rr_AverageAnnualReturnYear10

(3.75%)

02.28 Select Portfolios: Group 8 Materials Sector Retail Combo PRO-15 | Gold Portfolio | After Taxes on Distributions | Gold Portfolio

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Gold Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

35.41%

Past 5 years

rr_AverageAnnualReturnYear05

8.81%

Past 10 years

rr_AverageAnnualReturnYear10

(4.22%)

02.28 Select Portfolios: Group 8 Materials Sector Retail Combo PRO-15 | Gold Portfolio | After Taxes on Distributions and Sales | Gold Portfolio

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Gold Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions and Sale of Fund Shares</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

21.15%

Past 5 years

rr_AverageAnnualReturnYear05

7.09%

Past 10 years

rr_AverageAnnualReturnYear10

(2.61%)

02.28 Select Portfolios: Group 8 Materials Sector Retail Combo PRO-15 | Gold Portfolio | S&P 500® Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

31.49%

Past 5 years

rr_AverageAnnualReturnYear05

11.70%

Past 10 years

rr_AverageAnnualReturnYear10

13.56%

02.28 Select Portfolios: Group 8 Materials Sector Retail Combo PRO-15 | Gold Portfolio | S&P® Global BMI Gold Capped 20/45 Linked Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

45.04%

Past 5 years

rr_AverageAnnualReturnYear05

13.19%

Past 10 years

rr_AverageAnnualReturnYear10

(2.52%)

XML

Total

02.28 Select Portfolios: Group 3 Energy Sector Combo PRO-13 | Natural Resources Portfolio

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: bold 12pt Arial, Helvetica, sans-serif;">Fund:<br/>Natural Resources Portfolio</p>

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

The fund seeks capital appreciation.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

Shareholder Fees {- Natural Resources Portfolio}	02.28 Select Portfolios: Group 3 Energy Sector Combo PRO-13 Natural Resources Portfolio USD ($)
(fees paid directly from your investment)	none

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Annual Operating Expenses {- Natural Resources Portfolio}	02.28 Select Portfolios: Group 3 Energy Sector Combo PRO-13 Natural Resources Portfolio Natural Resources Portfolio-Default
Management fee	0.54%
Distribution and/or Service (12b-1) fees	none
Other expenses	0.30%
Total annual operating expenses	0.84%

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Expense Example {- Natural Resources Portfolio}	02.28 Select Portfolios: Group 3 Energy Sector Combo PRO-13 Natural Resources Portfolio Natural Resources Portfolio-Default USD ($)
1 year	$ 86
3 years	268
5 years	466
10 years	$ 1,037

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 8% of the average value of its portfolio.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

• Normally investing primarily in common stocks and in certain precious metals.

• Normally investing at least 80% of assets in securities of companies principally engaged in owning or developing natural resources, or supplying goods and services to such companies, and in precious metals.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Geographic Concentration in Canada. Because the fund concentrates its investments in Canada, the fund's performance is expected to be closely tied to social, political, and economic conditions within Canada and to be more volatile than the performance of more geographically diversified funds. In addition, because the fund may invest a significant percentage of assets in certain industries, the fund's performance could be affected to the extent that the particular industry or industries in which the fund invests are sensitive to adverse social, political, economic, currency, or regulatory developments.

• Natural Resources Industry Concentration. The natural resources industries can be significantly affected by events relating to international political and economic developments, energy conservation, the success of exploration projects, commodity prices, and tax and other government regulations.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	24.75%	December 31, 2010
Lowest Quarter Return	-25.64%	September 30, 2011
Year-to-Date Return	-48.28%	March 31, 2020

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

Average Annual Total Returns{- Natural Resources Portfolio} - 02.28 Select Portfolios: Group 3 Energy Sector Combo PRO-13 - Natural Resources Portfolio	Past 1 year	Past 5 years	Past 10 years
Natural Resources Portfolio-Default | Return Before Taxes	19.08%	(1.66%)	0.91%
Natural Resources Portfolio-Default | After Taxes on Distributions	18.67%	(1.91%)	0.54%
Natural Resources Portfolio-Default | After Taxes on Distributions and Sales	11.57%	(1.26%)	0.74%
S&P 500® Index(reflects no deduction for fees, expenses, or taxes)	31.49%	11.70%	13.56%
S&P® North American Natural Resources Sector Index(reflects no deduction for fees, expenses, or taxes)	17.63%	(1.41%)	1.39%

XML

Label

Element

Value

Risk/Return:

rr_RiskReturnAbstract

Registrant Name

dei_EntityRegistrantName

FIDELITY SELECT PORTFOLIOS

Prospectus Date

rr_ProspectusDate

Apr. 29, 2020

02.28 Select Portfolios: Fidelity Advisor Telecommunications Fund AMCIZ PRO-11 | Telecommunications Portfolio

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: normal 12pt Arial, Helvetica, sans-serif;"><b>Fund/Class</b>:<br/><b>Telecommunications Portfolio</b>/Fidelity Advisor® Telecommunications Fund A, M, C, I, Z</p>

Objective [Heading]

rr_ObjectiveHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks capital appreciation.

Expense [Heading]

rr_ExpenseHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund. In addition to the fees and expenses described below, your broker may also require you to pay brokerage commissions on purchases and sales of certain share classes of the fund.

You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $50,000 in the fund or certain other Fidelity^® funds. More information about these and other discounts is available from your investment professional and in the "Fund Distribution" section beginning on page 27 of the prospectus. Different intermediaries may provide additional waivers or reductions of the sales charge. Please see “Sales Charge Waiver Policies Applied by Certain Intermediaries” in the “Appendix” section of the prospectus.

Shareholder Fees Caption [Text]

rr_ShareholderFeesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(fees paid directly from your investment)</p>

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

Portfolio Turnover [Text Block]

rr_PortfolioTurnoverTextBlock

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 58% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

58.00%

Expense Breakpoint Discounts [Text]

rr_ExpenseBreakpointDiscounts

<font style="FONT-FAMILY: Times New Roman" size="3">You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $50,000 in the fund or certain other Fidelity® funds. More information about these and other discounts is available from your investment professional and in the "Fund Distribution" section beginning on page 27 of the prospectus.</font>

Expense Breakpoint, Minimum Investment Required [Amount]

rr_ExpenseBreakpointMinimumInvestmentRequiredAmount

$ 50,000

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated and if you hold your shares:

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Expense Example, No Redemption, By Year, Caption [Text]

rr_ExpenseExampleNoRedemptionByYearCaption

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Hold Shares</p>

Strategy [Heading]

rr_StrategyHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in the development, production, or distribution of telecommunications services.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

Strategy Portfolio Concentration [Text]

rr_StrategyPortfolioConcentration

<font style="FONT-FAMILY: Times New Roman" size="3">Normally investing at least 80% of assets in securities of companies principally engaged in the development, production, or distribution of telecommunications services.</font>

Risk [Heading]

rr_RiskHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Telecom Services Industry Concentration. The telecom services industry is subject to government regulation and can be significantly affected by intense competition and technology changes.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

Risk Lose Money [Text]

rr_RiskLoseMoney

<font style="FONT-FAMILY: Times New Roman" size="3">You could lose money by investing in the fund.</font>

Risk Nondiversified Status [Text]

rr_RiskNondiversifiedStatus

<font style="FONT-FAMILY: Times New Roman" size="3">In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.</font>

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

<font style="FONT-FAMILY: Times New Roman" size="3">An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</font>

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit institutional.fidelity.com for more recent performance information.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

<font style="FONT-FAMILY: Times New Roman" size="3">The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time.</font>

Performance Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

<font style="FONT-FAMILY: Times New Roman" size="3">institutional.fidelity.com </font>

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

<font style="FONT-FAMILY: Times New Roman" size="3">Past performance (before and after taxes) is not an indication of future performance.</font>

Bar Chart [Heading]

rr_BarChartHeading

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

Bar Chart Narrative [Text Block]

rr_BarChartNarrativeTextBlock

The returns in the bar chart do not reflect any applicable sales charges; if sales charges were reflected, returns would be lower than those shown.

Bar Chart Does Not Reflect Sales Loads [Text]

rr_BarChartDoesNotReflectSalesLoads

<font style="FONT-FAMILY: Times New Roman" size="3">The returns in the bar chart do not reflect any applicable sales charges; if sales charges were reflected, returns would be lower than those shown.</font>

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

During the periods shown in the chart for Class A:	Returns	Quarter ended
Highest Quarter Return	17.53%	September 30, 2010
Lowest Quarter Return	-17.05%	September 30, 2011
Year-to-Date Return	-8.20%	March 31, 2020

Performance Table Heading

rr_PerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

Performance Table Does Reflect Sales Loads

rr_PerformanceTableDoesReflectSalesLoads

<font style="FONT-FAMILY: Times New Roman" size="3">Unlike the returns in the bar chart, the returns in the table reflect the maximum applicable sales charges.</font>

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

<font style="FONT-FAMILY: Times New Roman" size="3">After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes.</font>

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

<font style="FONT-FAMILY: Times New Roman" size="3">The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan).</font>

Performance Table One Class of after Tax Shown [Text]

rr_PerformanceTableOneClassOfAfterTaxShown

<font style="FONT-FAMILY: Times New Roman" size="3">After-tax returns for Class A are shown in the table below and after-tax returns for other classes will vary.</font>

Performance Table Explanation after Tax Higher

rr_PerformanceTableExplanationAfterTaxHigher

<font style="FONT-FAMILY: Times New Roman" size="3">Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.</font>

Performance Table Narrative

rr_PerformanceTableNarrativeTextBlock

Unlike the returns in the bar chart, the returns in the table reflect the maximum applicable sales charges. After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. After-tax returns for Class A are shown in the table below and after-tax returns for other classes will vary. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

02.28 Select Portfolios: Fidelity Advisor Telecommunications Fund AMCIZ PRO-11 | Telecommunications Portfolio | Fidelity Advisor Telecommunications Fund: Class A

Risk/Return:

rr_RiskReturnAbstract

Maximum sales charge (load) on purchases (as a % of offering price)

rr_MaximumCumulativeSalesChargeOverOfferingPrice

5.75%

Maximum contingent deferred sales charge (as a % of the lesser of original purchase price or redemption proceeds)

rr_MaximumDeferredSalesChargeOverOther

none

^[1]

Management fee

rr_ManagementFeesOverAssets

0.54%

Distribution and/or Service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

0.25%

Other expenses

rr_OtherExpensesOverAssets

0.39%

Total annual operating expenses

rr_ExpensesOverAssets

1.18%

Expenses Deferred Charges [Text Block]

rr_ExpensesDeferredChargesTextBlock

Class A and Class M purchases of $1 million or more will not be subject to a front-end sales charge. Such Class A and Class M purchases may be subject, upon redemption, to a contingent deferred sales charge (CDSC) of 1.00% or 0.25%, respectively.

1 year

rr_ExpenseExampleYear01

$ 688

3 years

rr_ExpenseExampleYear03

928

5 years

rr_ExpenseExampleYear05

1,187

10 years

rr_ExpenseExampleYear10

1,924

1 Year

rr_ExpenseExampleNoRedemptionYear01

688

3 Years

rr_ExpenseExampleNoRedemptionYear03

928

5 Years

rr_ExpenseExampleNoRedemptionYear05

1,187

10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 1,924

2010

rr_AnnualReturn2010

18.01%

2011

rr_AnnualReturn2011

(4.52%)

2012

rr_AnnualReturn2012

18.27%

2013

rr_AnnualReturn2013

21.12%

2014

rr_AnnualReturn2014

3.27%

2015

rr_AnnualReturn2015

1.96%

2016

rr_AnnualReturn2016

22.39%

2017

rr_AnnualReturn2017

1.37%

2018

rr_AnnualReturn2018

(8.33%)

2019

rr_AnnualReturn2019

19.96%

Year to Date Return, Label

rr_YearToDateReturnLabel

Year-to-Date Return

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Mar. 31, 2020

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

(8.20%)

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Highest Quarter Return

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Sep. 30, 2010

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

17.53%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Lowest Quarter Return

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Sep. 30, 2011

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(17.05%)

02.28 Select Portfolios: Fidelity Advisor Telecommunications Fund AMCIZ PRO-11 | Telecommunications Portfolio | Fidelity Advisor Telecommunications Fund: Class M

Risk/Return:

rr_RiskReturnAbstract

Maximum sales charge (load) on purchases (as a % of offering price)

rr_MaximumCumulativeSalesChargeOverOfferingPrice

3.50%

Maximum contingent deferred sales charge (as a % of the lesser of original purchase price or redemption proceeds)

rr_MaximumDeferredSalesChargeOverOther

none

^[1]

Management fee

rr_ManagementFeesOverAssets

0.54%

Distribution and/or Service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

0.50%

Other expenses

rr_OtherExpensesOverAssets

0.42%

Total annual operating expenses

rr_ExpensesOverAssets

1.46%

Expenses Deferred Charges [Text Block]

rr_ExpensesDeferredChargesTextBlock

Class A and Class M purchases of $1 million or more will not be subject to a front-end sales charge. Such Class A and Class M purchases may be subject, upon redemption, to a contingent deferred sales charge (CDSC) of 1.00% or 0.25%, respectively.

1 year

rr_ExpenseExampleYear01

$ 493

3 years

rr_ExpenseExampleYear03

796

5 years

rr_ExpenseExampleYear05

1,120

10 years

rr_ExpenseExampleYear10

2,035

1 Year

rr_ExpenseExampleNoRedemptionYear01

493

3 Years

rr_ExpenseExampleNoRedemptionYear03

796

5 Years

rr_ExpenseExampleNoRedemptionYear05

1,120

10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 2,035

02.28 Select Portfolios: Fidelity Advisor Telecommunications Fund AMCIZ PRO-11 | Telecommunications Portfolio | Fidelity Advisor Telecommunications Fund: Class C

Risk/Return:

rr_RiskReturnAbstract

Maximum sales charge (load) on purchases (as a % of offering price)

rr_MaximumCumulativeSalesChargeOverOfferingPrice

none

Maximum contingent deferred sales charge (as a % of the lesser of original purchase price or redemption proceeds)

rr_MaximumDeferredSalesChargeOverOther

1.00%

^[2]

Management fee

rr_ManagementFeesOverAssets

0.54%

Distribution and/or Service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

1.00%

Other expenses

rr_OtherExpensesOverAssets

0.34%

Total annual operating expenses

rr_ExpensesOverAssets

1.88%

Expenses Deferred Charges [Text Block]

rr_ExpensesDeferredChargesTextBlock

On Class C shares redeemed less than one year after purchase.

1 year

rr_ExpenseExampleYear01

$ 291

3 years

rr_ExpenseExampleYear03

591

5 years

rr_ExpenseExampleYear05

1,016

10 years

rr_ExpenseExampleYear10

2,201

1 Year

rr_ExpenseExampleNoRedemptionYear01

191

3 Years

rr_ExpenseExampleNoRedemptionYear03

591

5 Years

rr_ExpenseExampleNoRedemptionYear05

1,016

10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 2,201

02.28 Select Portfolios: Fidelity Advisor Telecommunications Fund AMCIZ PRO-11 | Telecommunications Portfolio | Fidelity Advisor Telecommunications Fund: Class I

Risk/Return:

rr_RiskReturnAbstract

Maximum sales charge (load) on purchases (as a % of offering price)

rr_MaximumCumulativeSalesChargeOverOfferingPrice

none

Maximum contingent deferred sales charge (as a % of the lesser of original purchase price or redemption proceeds)

rr_MaximumDeferredSalesChargeOverOther

none

Management fee

rr_ManagementFeesOverAssets

0.54%

Distribution and/or Service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

none

Other expenses

rr_OtherExpensesOverAssets

0.34%

Total annual operating expenses

rr_ExpensesOverAssets

0.88%

1 year

rr_ExpenseExampleYear01

$ 90

3 years

rr_ExpenseExampleYear03

281

5 years

rr_ExpenseExampleYear05

488

10 years

rr_ExpenseExampleYear10

1,084

1 Year

rr_ExpenseExampleNoRedemptionYear01

90

3 Years

rr_ExpenseExampleNoRedemptionYear03

281

5 Years

rr_ExpenseExampleNoRedemptionYear05

488

10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 1,084

02.28 Select Portfolios: Fidelity Advisor Telecommunications Fund AMCIZ PRO-11 | Telecommunications Portfolio | Fidelity Advisor Telecommunications Fund: Class Z

Risk/Return:

rr_RiskReturnAbstract

Maximum sales charge (load) on purchases (as a % of offering price)

rr_MaximumCumulativeSalesChargeOverOfferingPrice

none

Maximum contingent deferred sales charge (as a % of the lesser of original purchase price or redemption proceeds)

rr_MaximumDeferredSalesChargeOverOther

none

Management fee

rr_ManagementFeesOverAssets

0.54%

Distribution and/or Service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

none

Other expenses

rr_OtherExpensesOverAssets

0.14%

Total annual operating expenses

rr_ExpensesOverAssets

0.68%

1 year

rr_ExpenseExampleYear01

$ 69

3 years

rr_ExpenseExampleYear03

218

5 years

rr_ExpenseExampleYear05

379

10 years

rr_ExpenseExampleYear10

847

1 Year

rr_ExpenseExampleNoRedemptionYear01

69

3 Years

rr_ExpenseExampleNoRedemptionYear03

218

5 Years

rr_ExpenseExampleNoRedemptionYear05

379

10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 847

02.28 Select Portfolios: Fidelity Advisor Telecommunications Fund AMCIZ PRO-11 | Telecommunications Portfolio | Return Before Taxes | Fidelity Advisor Telecommunications Fund: Class A

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Telecommunications Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Class A - Return Before Taxes</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

13.07%

Past 5 years

rr_AverageAnnualReturnYear05

5.57%

Past 10 years

rr_AverageAnnualReturnYear10

8.13%

02.28 Select Portfolios: Fidelity Advisor Telecommunications Fund AMCIZ PRO-11 | Telecommunications Portfolio | Return Before Taxes | Fidelity Advisor Telecommunications Fund: Class M

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Telecommunications Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Class M - Return Before Taxes</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

15.44%

Past 5 years

rr_AverageAnnualReturnYear05

5.73%

Past 10 years

rr_AverageAnnualReturnYear10

8.05%

02.28 Select Portfolios: Fidelity Advisor Telecommunications Fund AMCIZ PRO-11 | Telecommunications Portfolio | Return Before Taxes | Fidelity Advisor Telecommunications Fund: Class C

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Telecommunications Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Class C - Return Before Taxes</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

18.14%

Past 5 years

rr_AverageAnnualReturnYear05

6.06%

Past 10 years

rr_AverageAnnualReturnYear10

7.99%

02.28 Select Portfolios: Fidelity Advisor Telecommunications Fund AMCIZ PRO-11 | Telecommunications Portfolio | Return Before Taxes | Fidelity Advisor Telecommunications Fund: Class I

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Telecommunications Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Class I - Return Before Taxes</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

20.33%

Past 5 years

rr_AverageAnnualReturnYear05

7.17%

Past 10 years

rr_AverageAnnualReturnYear10

9.11%

02.28 Select Portfolios: Fidelity Advisor Telecommunications Fund AMCIZ PRO-11 | Telecommunications Portfolio | Return Before Taxes | Fidelity Advisor Telecommunications Fund: Class Z

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Telecommunications Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Class Z - Return Before Taxes</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

20.58%

Past 10 years

rr_AverageAnnualReturnYear10

Since Inception

rr_AverageAnnualReturnSinceInception

4.31%

^[3]

Inception Date

rr_AverageAnnualReturnInceptionDate

Oct. 02, 2018

02.28 Select Portfolios: Fidelity Advisor Telecommunications Fund AMCIZ PRO-11 | Telecommunications Portfolio | After Taxes on Distributions | Fidelity Advisor Telecommunications Fund: Class A

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Telecommunications Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

12.28%

Past 5 years

rr_AverageAnnualReturnYear05

3.95%

Past 10 years

rr_AverageAnnualReturnYear10

7.09%

02.28 Select Portfolios: Fidelity Advisor Telecommunications Fund AMCIZ PRO-11 | Telecommunications Portfolio | After Taxes on Distributions and Sales | Fidelity Advisor Telecommunications Fund: Class A

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Telecommunications Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions and Sale of Fund Shares</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

8.29%

Past 5 years

rr_AverageAnnualReturnYear05

4.13%

Past 10 years

rr_AverageAnnualReturnYear10

6.49%

02.28 Select Portfolios: Fidelity Advisor Telecommunications Fund AMCIZ PRO-11 | Telecommunications Portfolio | S&P 500® Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

31.49%

Past 5 years

rr_AverageAnnualReturnYear05

11.70%

Past 10 years

rr_AverageAnnualReturnYear10

13.56%

02.28 Select Portfolios: Fidelity Advisor Telecommunications Fund AMCIZ PRO-11 | Telecommunications Portfolio | MSCI U.S. IM Telecommunication Services 25-50 Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

12.64%

Past 5 years

rr_AverageAnnualReturnYear05

4.11%

Past 10 years

rr_AverageAnnualReturnYear10

7.99%

[1] Class A and Class M purchases of $1 million or more will not be subject to a front-end sales charge. Such Class A and Class M purchases may be subject, upon redemption, to a contingent deferred sales charge (CDSC) of 1.00% or 0.25%, respectively.

[2] On Class C shares redeemed less than one year after purchase.

[3] Since inception October 2, 2018.

XML

Total

02.28 Select Portfolios: Fidelity Advisor Materials Fund - AMCIZ PRO-12 | Materials Portfolio

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: normal 12pt Arial, Helvetica, sans-serif;"><b>Fund/Class</b>:<br/><b>Materials Portfolio</b>/Fidelity Advisor® Materials Fund A, M, C, I, Z</p>

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

The fund seeks capital appreciation.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund. In addition to the fees and expenses described below, your broker may also require you to pay brokerage commissions on purchases and sales of certain share classes of the fund.

You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $50,000 in the fund or certain other Fidelity^® funds. More information about these and other discounts is available from your investment professional and in the "Fund Distribution" section beginning on page 28 of the prospectus. Different intermediaries may provide additional waivers or reductions of the sales charge. Please see “Sales Charge Waiver Policies Applied by Certain Intermediaries” in the “Appendix” section of the prospectus.

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(fees paid directly from your investment)</p>

Shareholder Fees {- Materials Portfolio} - 02.28 Select Portfolios: Fidelity Advisor Materials Fund - AMCIZ PRO-12 - Materials Portfolio	Fidelity Advisor Materials Fund: Class A		Fidelity Advisor Materials Fund: Class M		Fidelity Advisor Materials Fund: Class C		Fidelity Advisor Materials Fund: Class I	Fidelity Advisor Materials Fund: Class Z
Maximum sales charge (load) on purchases (as a % of offering price)	5.75%		3.50%		none		none	none
Maximum contingent deferred sales charge (as a % of the lesser of original purchase price or redemption proceeds)	none	[1]	none	[1]	1.00%	[2]	none	none

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Annual Operating Expenses {- Materials Portfolio} - 02.28 Select Portfolios: Fidelity Advisor Materials Fund - AMCIZ PRO-12 - Materials Portfolio	Fidelity Advisor Materials Fund: Class A	Fidelity Advisor Materials Fund: Class M	Fidelity Advisor Materials Fund: Class C	Fidelity Advisor Materials Fund: Class I	Fidelity Advisor Materials Fund: Class Z
Management fee	0.53%	0.53%	0.53%	0.53%	0.53%
Distribution and/or Service (12b-1) fees	0.25%	0.50%	1.00%	none	none
Other expenses	0.30%	0.34%	0.29%	0.26%	0.10%
Total annual operating expenses	1.08%	1.37%	1.82%	0.79%	0.63%

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated and if you hold your shares:

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Expense Example {- Materials Portfolio} - 02.28 Select Portfolios: Fidelity Advisor Materials Fund - AMCIZ PRO-12 - Materials Portfolio - USD ($)	Fidelity Advisor Materials Fund: Class A	Fidelity Advisor Materials Fund: Class M	Fidelity Advisor Materials Fund: Class C	Fidelity Advisor Materials Fund: Class I	Fidelity Advisor Materials Fund: Class Z
1 year	$ 679	$ 485	$ 285	$ 81	$ 64
3 years	899	769	573	252	202
5 years	1,136	1,074	985	439	351
10 years	$ 1,816	$ 1,939	$ 2,137	$ 978	$ 786

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Hold Shares</p>

Expense Example, No Redemption {- Materials Portfolio} - 02.28 Select Portfolios: Fidelity Advisor Materials Fund - AMCIZ PRO-12 - Materials Portfolio - USD ($)	Fidelity Advisor Materials Fund: Class A	Fidelity Advisor Materials Fund: Class M	Fidelity Advisor Materials Fund: Class C	Fidelity Advisor Materials Fund: Class I	Fidelity Advisor Materials Fund: Class Z
1 Year	$ 679	$ 485	$ 185	$ 81	$ 64
3 Years	899	769	573	252	202
5 Years	1,136	1,074	985	439	351
10 Years	$ 1,816	$ 1,939	$ 2,137	$ 978	$ 786

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 69% of the average value of its portfolio.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in the manufacture, mining, processing, or distribution of raw materials and intermediate goods.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Materials Industry Concentration. The materials industries can be significantly affected by the level and volatility of commodity prices, the exchange value of the dollar, import and export controls, worldwide competition, liability for environmental damage, depletion of resources, and mandated expenditures for safety and pollution control.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit institutional.fidelity.com for more recent performance information.

The returns in the bar chart do not reflect any applicable sales charges; if sales charges were reflected, returns would be lower than those shown.

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

During the periods shown in the chart for Class A:	Returns	Quarter ended
Highest Quarter Return	20.81%	December 31, 2010
Lowest Quarter Return	-25.35%	September 30, 2011
Year-to-Date Return	-26.36%	March 31, 2020

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

Unlike the returns in the bar chart, the returns in the table reflect the maximum applicable sales charges. After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. After-tax returns for Class A are shown in the table below and after-tax returns for other classes will vary. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

Average Annual Total Returns{- Materials Portfolio} - 02.28 Select Portfolios: Fidelity Advisor Materials Fund - AMCIZ PRO-12 - Materials Portfolio	Past 1 year	Past 5 years	Past 10 years	Since Inception	[1]	Inception Date
Fidelity Advisor Materials Fund: Class A | Return Before Taxes	5.65%	0.60%	5.75%
Fidelity Advisor Materials Fund: Class A | After Taxes on Distributions	5.41%	(0.33%)	4.88%
Fidelity Advisor Materials Fund: Class A | After Taxes on Distributions and Sales	3.52%	0.46%	4.62%
Fidelity Advisor Materials Fund: Class M | Return Before Taxes	7.85%	0.77%	5.69%
Fidelity Advisor Materials Fund: Class C | Return Before Taxes	10.26%	1.04%	5.58%
Fidelity Advisor Materials Fund: Class I | Return Before Taxes	12.41%	2.09%	6.68%
Fidelity Advisor Materials Fund: Class Z | Return Before Taxes	12.59%			(5.69%)		Oct. 02, 2018
S&P 500® Index(reflects no deduction for fees, expenses, or taxes)	31.49%	11.70%	13.56%
MSCI U.S. IMI Materials 25-50 Index(reflects no deduction for fees, expenses, or taxes)	23.80%	6.70%	9.30%

02.28 Select Portfolios: Fidelity Advisor Materials Fund - AMCIZ PRO-12 | Materials Portfolio | Fidelity Advisor Materials Fund: Class A

Class A and Class M purchases of $1 million or more will not be subject to a front-end sales charge. Such Class A and Class M purchases may be subject, upon redemption, to a contingent deferred sales charge (CDSC) of 1.00% or 0.25%, respectively.

02.28 Select Portfolios: Fidelity Advisor Materials Fund - AMCIZ PRO-12 | Materials Portfolio | Fidelity Advisor Materials Fund: Class M

Class A and Class M purchases of $1 million or more will not be subject to a front-end sales charge. Such Class A and Class M purchases may be subject, upon redemption, to a contingent deferred sales charge (CDSC) of 1.00% or 0.25%, respectively.

02.28 Select Portfolios: Fidelity Advisor Materials Fund - AMCIZ PRO-12 | Materials Portfolio | Fidelity Advisor Materials Fund: Class C

On Class C shares redeemed less than one year after purchase.

[1] Class A and Class M purchases of $1 million or more will not be subject to a front-end sales charge. Such Class A and Class M purchases may be subject, upon redemption, to a contingent deferred sales charge (CDSC) of 1.00% or 0.25%, respectively.

[2] On Class C shares redeemed less than one year after purchase.

[1] Since inception October 2, 2018.

XML

Total

02.28 Select Portfolios: Group 4 Financials Sector Combo PRO-15 | Consumer Finance Portfolio

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: bold 12pt Arial, Helvetica, sans-serif;">Fund:<br/>Consumer Finance Portfolio</p>

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

The fund seeks capital appreciation.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

Shareholder Fees {- Consumer Finance Portfolio}	02.28 Select Portfolios: Group 4 Financials Sector Combo PRO-15 Consumer Finance Portfolio USD ($)
(fees paid directly from your investment)	none

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Annual Operating Expenses {- Consumer Finance Portfolio}	02.28 Select Portfolios: Group 4 Financials Sector Combo PRO-15 Consumer Finance Portfolio Consumer Finance Portfolio-Default
Management fee	0.54%
Distribution and/or Service (12b-1) fees	none
Other expenses	0.32%
Total annual operating expenses	0.86%

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Expense Example {- Consumer Finance Portfolio}	02.28 Select Portfolios: Group 4 Financials Sector Combo PRO-15 Consumer Finance Portfolio Consumer Finance Portfolio-Default USD ($)
1 year	$ 88
3 years	274
5 years	477
10 years	$ 1,061

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 20% of the average value of its portfolio.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in providing products and services associated with consumer finance.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Consumer Finance Industry Concentration. The consumer finance industry can be significantly affected by changing economic conditions, demand for consumer loans, refinancing activity, interest rate changes, and government regulation.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Prior to December 1, 2010, the fund was named Home Finance Portfolio, and the fund operated under certain different investment policies and compared its performance to a different additional index. The fund's historical performance may not represent its current investment policies. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	21.38%	March 31, 2012
Lowest Quarter Return	-15.24%	December 31, 2018
Year-to-Date Return	-41.08%	March 31, 2020

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

Average Annual Total Returns{- Consumer Finance Portfolio} - 02.28 Select Portfolios: Group 4 Financials Sector Combo PRO-15 - Consumer Finance Portfolio	Past 1 year	Past 5 years	Past 10 years
Consumer Finance Portfolio-Default | Return Before Taxes	34.18%	10.02%	12.43%
Consumer Finance Portfolio-Default | After Taxes on Distributions	33.55%	8.63%	10.48%
Consumer Finance Portfolio-Default | After Taxes on Distributions and Sales	20.56%	7.55%	9.65%
S&P 500® Index(reflects no deduction for fees, expenses, or taxes)	31.49%	11.70%	13.56%
S&P® Consumer Finance Index(reflects no deduction for fees, expenses, or taxes)	33.04%	8.85%	11.64%

XML

Total

02.28 Select Portfolios: Fidelity Advisor Gold Fund - AMCIZ PRO-12 | Gold Portfolio

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: normal 12pt Arial, Helvetica, sans-serif;"><b>Fund/Class</b>:<br/><b>Gold Portfolio</b>/Fidelity Advisor® Gold Fund A, M, C, I, Z</p>

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

The fund seeks capital appreciation.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund. In addition to the fees and expenses described below, your broker may also require you to pay brokerage commissions on purchases and sales of certain share classes of the fund.

You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $50,000 in the fund or certain other Fidelity^® funds. More information about these and other discounts is available from your investment professional and in the "Fund Distribution" section beginning on page 29 of the prospectus. Different intermediaries may provide additional waivers or reductions of the sales charge. Please see “Sales Charge Waiver Policies Applied by Certain Intermediaries” in the “Appendix” section of the prospectus.

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(fees paid directly from your investment)</p>

Shareholder Fees {- Gold Portfolio} - 02.28 Select Portfolios: Fidelity Advisor Gold Fund - AMCIZ PRO-12 - Gold Portfolio	Fidelity Advisor Gold Fund: Class A		Fidelity Advisor Gold Fund: Class M		Fidelity Advisor Gold Fund: Class C		Fidelity Advisor Gold Fund: Class I	Fidelity Advisor Gold Fund: Class Z
Maximum sales charge (load) on purchases (as a % of offering price)	5.75%		3.50%		none		none	none
Maximum contingent deferred sales charge (as a % of the lesser of original purchase price or redemption proceeds)	none	[1]	none	[1]	1.00%	[2]	none	none

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Annual Operating Expenses {- Gold Portfolio} - 02.28 Select Portfolios: Fidelity Advisor Gold Fund - AMCIZ PRO-12 - Gold Portfolio	Fidelity Advisor Gold Fund: Class A	Fidelity Advisor Gold Fund: Class M	Fidelity Advisor Gold Fund: Class C	Fidelity Advisor Gold Fund: Class I	Fidelity Advisor Gold Fund: Class Z
Management fee	0.54%	0.54%	0.54%	0.54%	0.54%
Distribution and/or Service (12b-1) fees	0.25%	0.50%	1.00%	none	none
Other expenses	0.34%	0.38%	0.26%	0.25%	0.11%
Total annual operating expenses	1.13%	1.42%	1.80%	0.79%	0.65%

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated and if you hold your shares:

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Expense Example {- Gold Portfolio} - 02.28 Select Portfolios: Fidelity Advisor Gold Fund - AMCIZ PRO-12 - Gold Portfolio - USD ($)	Fidelity Advisor Gold Fund: Class A	Fidelity Advisor Gold Fund: Class M	Fidelity Advisor Gold Fund: Class C	Fidelity Advisor Gold Fund: Class I	Fidelity Advisor Gold Fund: Class Z
1 year	$ 684	$ 489	$ 283	$ 81	$ 66
3 years	913	784	566	252	208
5 years	1,161	1,099	975	439	362
10 years	$ 1,871	$ 1,992	$ 2,116	$ 978	$ 810

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Hold Shares</p>

Expense Example, No Redemption {- Gold Portfolio} - 02.28 Select Portfolios: Fidelity Advisor Gold Fund - AMCIZ PRO-12 - Gold Portfolio - USD ($)	Fidelity Advisor Gold Fund: Class A	Fidelity Advisor Gold Fund: Class M	Fidelity Advisor Gold Fund: Class C	Fidelity Advisor Gold Fund: Class I	Fidelity Advisor Gold Fund: Class Z
1 Year	$ 684	$ 489	$ 183	$ 81	$ 66
3 Years	913	784	566	252	208
5 Years	1,161	1,099	975	439	362
10 Years	$ 1,871	$ 1,992	$ 2,116	$ 978	$ 810

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 56% of the average value of its portfolio.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

• Normally investing primarily in common stocks and in certain precious metals.

• Investing primarily in companies engaged in exploration, mining, processing, or dealing in gold, or to a lesser degree, in silver, platinum, diamonds, or other precious metals and minerals.

• Normally investing at least 80% of assets in securities of companies principally engaged in gold-related activities, and in gold bullion or coins.

• Investing up to 25% of assets in gold and other precious metals through a wholly-owned subsidiary organized under the laws of the Cayman Islands.

• Potentially investing in other precious metals, instruments whose value is linked to the price of precious metals, and securities of companies that manufacture and distribute precious metal and minerals products (such as jewelry, watches, and metal foil and leaf) and companies that invest in other companies engaged in gold and other precious metal and mineral-related activities.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets, particularly emerging markets, can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market. Emerging markets can be subject to greater social, economic, regulatory, and political uncertainties and can be extremely volatile. Foreign exchange rates also can be extremely volatile.

• Geographic Concentration in Canada. Because an underlying fund concentrates its investments in Canada, the underlying fund's performance is expected to be closely tied to social, political, and economic conditions within Canada and to be more volatile than the performance of more geographically diversified funds. In addition, because the underlying fund may invest a significant percentage of assets in certain industries, the underlying fund's performance could be affected to the extent that the particular industry or industries in which the fund invests are sensitive to adverse social, political, economic, currency, or regulatory developments.

• Gold Industry Concentration. The gold industry can be significantly affected by international monetary and political developments such as currency devaluations or revaluations, central bank movements, economic and social conditions within a country, trade imbalances, or trade or currency restrictions between countries, as well as supply and demand for gold and operational costs associated with mining.

• Subsidiary Risk. Investment in Fidelity Select Gold Cayman Ltd., an unregistered subsidiary, is not subject to the investor protections of the Investment Company Act of 1940 (1940 Act) and is subject to the risks associated with the gold industry. Changes in tax and other laws could negatively affect investments in the subsidiary.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the 1940 Act, which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit institutional.fidelity.com for more recent performance information.

The returns in the bar chart do not reflect any applicable sales charges; if sales charges were reflected, returns would be lower than those shown.

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

During the periods shown in the chart for Class A:	Returns	Quarter ended
Highest Quarter Return	40.94%	March 31, 2016
Lowest Quarter Return	-37.42%	June 30, 2013
Year-to-Date Return	-19.14%	March 31, 2020

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

Unlike the returns in the bar chart, the returns in the table reflect the maximum applicable sales charges. After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. After-tax returns for Class A are shown in the table below and after-tax returns for other classes will vary. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

Average Annual Total Returns{- Gold Portfolio} - 02.28 Select Portfolios: Fidelity Advisor Gold Fund - AMCIZ PRO-12 - Gold Portfolio	Past 1 year	Past 5 years	Past 10 years	Since Inception	[1]	Inception Date
Fidelity Advisor Gold Fund: Class A | Return Before Taxes	27.29%	7.53%	(4.60%)
Fidelity Advisor Gold Fund: Class A | After Taxes on Distributions	27.28%	7.25%	(5.04%)
Fidelity Advisor Gold Fund: Class A | After Taxes on Distributions and Sales	16.24%	5.80%	(3.17%)
Fidelity Advisor Gold Fund: Class M | Return Before Taxes	29.92%	7.72%	(4.64%)
Fidelity Advisor Gold Fund: Class C | Return Before Taxes	33.09%	8.06%	(4.71%)
Fidelity Advisor Gold Fund: Class I | Return Before Taxes	35.50%	9.16%	(3.71%)
Fidelity Advisor Gold Fund: Class Z | Return Before Taxes	35.74%			36.65%		Oct. 02, 2018
S&P 500® Index(reflects no deduction for fees, expenses, or taxes)	31.49%	11.70%	13.56%
S&P® Global BMI Gold Capped 20/45 Linked Index(reflects no deduction for fees, expenses, or taxes)	45.04%	13.19%	(2.52%)

02.28 Select Portfolios: Fidelity Advisor Gold Fund - AMCIZ PRO-12 | Gold Portfolio | Fidelity Advisor Gold Fund: Class A

Class A and Class M purchases of $1 million or more will not be subject to a front-end sales charge. Such Class A and Class M purchases may be subject, upon redemption, to a contingent deferred sales charge (CDSC) of 1.00% or 0.25%, respectively.

02.28 Select Portfolios: Fidelity Advisor Gold Fund - AMCIZ PRO-12 | Gold Portfolio | Fidelity Advisor Gold Fund: Class M

Class A and Class M purchases of $1 million or more will not be subject to a front-end sales charge. Such Class A and Class M purchases may be subject, upon redemption, to a contingent deferred sales charge (CDSC) of 1.00% or 0.25%, respectively.

02.28 Select Portfolios: Fidelity Advisor Gold Fund - AMCIZ PRO-12 | Gold Portfolio | Fidelity Advisor Gold Fund: Class C

On Class C shares redeemed less than one year after purchase.

[1] Class A and Class M purchases of $1 million or more will not be subject to a front-end sales charge. Such Class A and Class M purchases may be subject, upon redemption, to a contingent deferred sales charge (CDSC) of 1.00% or 0.25%, respectively.

[2] On Class C shares redeemed less than one year after purchase.

[1] Since inception October 2, 2018.

XML

Label

Element

Value

Risk/Return:

rr_RiskReturnAbstract

Registrant Name

dei_EntityRegistrantName

FIDELITY SELECT PORTFOLIOS

Prospectus Date

rr_ProspectusDate

Apr. 29, 2020

02.28 Select Portfolios: Group 7 Information Technology Sector Combo PRO-16 | Software and IT Services Portfolio

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: bold 12pt Arial, Helvetica, sans-serif;">Fund:<br/>Software and IT Services Portfolio</p>

Objective [Heading]

rr_ObjectiveHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks capital appreciation.

Expense [Heading]

rr_ExpenseHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

Shareholder Fees Caption [Text]

rr_ShareholderFeesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

(fees paid directly from your investment)

rr_ShareholderFeeOther

none

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

Portfolio Turnover [Text Block]

rr_PortfolioTurnoverTextBlock

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 23% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

23.00%

Expenses Not Correlated to Ratio Due to Acquired Fund Fees [Text]

rr_ExpensesNotCorrelatedToRatioDueToAcquiredFundFees

<font style="FONT-FAMILY: Times New Roman" size="3">Differs from the ratios of expenses to average net assets in the Financial Highlights section of the prospectus because of acquired fund fees and expenses. For the period, acquired fund fees and expenses are less than 0.01% and are included in other expenses.</font>

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Strategy [Heading]

rr_StrategyHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in research, design, production, or distribution of products or processes that relate to software or information-based services.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

Strategy Portfolio Concentration [Text]

rr_StrategyPortfolioConcentration

<font style="FONT-FAMILY: Times New Roman" size="3">Normally investing at least 80% of assets in securities of companies principally engaged in research, design, production, or distribution of products or processes that relate to software or information-based services.</font>

Risk [Heading]

rr_RiskHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Software and Information Technology Services Industry Concentration. The software and information technology services industry can be significantly affected by intense competition, aggressive pricing, technological innovations, and product obsolescence.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

Risk Lose Money [Text]

rr_RiskLoseMoney

<font style="FONT-FAMILY: Times New Roman" size="3">You could lose money by investing in the fund.</font>

Risk Nondiversified Status [Text]

rr_RiskNondiversifiedStatus

<font style="FONT-FAMILY: Times New Roman" size="3">In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.</font>

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

<font style="FONT-FAMILY: Times New Roman" size="3">An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</font>

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

<font style="FONT-FAMILY: Times New Roman" size="3">The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time.</font>

Performance Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

<font style="FONT-FAMILY: Times New Roman" size="3">www.fidelity.com </font>

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

<font style="FONT-FAMILY: Times New Roman" size="3">Past performance (before and after taxes) is not an indication of future performance.</font>

Bar Chart [Heading]

rr_BarChartHeading

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	20.44%	March 31, 2012
Lowest Quarter Return	-14.71%	December 31, 2018
Year-to-Date Return	-10.24%	March 31, 2020

Performance Table Heading

rr_PerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

<font style="FONT-FAMILY: Times New Roman" size="3">After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes.</font>

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

<font style="FONT-FAMILY: Times New Roman" size="3">The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan).</font>

Performance Table Explanation after Tax Higher

rr_PerformanceTableExplanationAfterTaxHigher

<font style="FONT-FAMILY: Times New Roman" size="3">Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.</font>

Performance Table Narrative

rr_PerformanceTableNarrativeTextBlock

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

02.28 Select Portfolios: Group 7 Information Technology Sector Combo PRO-16 | Software and IT Services Portfolio | Software and IT Services Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Management fee

rr_ManagementFeesOverAssets

0.54%

Distribution and/or Service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

none

Other expenses

rr_OtherExpensesOverAssets

0.17%

^[1]

Total annual operating expenses

rr_ExpensesOverAssets

0.71%

1 year

rr_ExpenseExampleYear01

$ 73

3 years

rr_ExpenseExampleYear03

227

5 years

rr_ExpenseExampleYear05

395

10 years

rr_ExpenseExampleYear10

$ 883

2010

rr_AnnualReturn2010

18.94%

2011

rr_AnnualReturn2011

2.18%

2012

rr_AnnualReturn2012

18.06%

2013

rr_AnnualReturn2013

51.12%

2014

rr_AnnualReturn2014

8.22%

2015

rr_AnnualReturn2015

10.47%

2016

rr_AnnualReturn2016

10.31%

2017

rr_AnnualReturn2017

38.53%

2018

rr_AnnualReturn2018

4.19%

2019

rr_AnnualReturn2019

38.87%

Year to Date Return, Label

rr_YearToDateReturnLabel

Year-to-Date Return

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Mar. 31, 2020

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

(10.24%)

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Highest Quarter Return

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Mar. 31, 2012

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

20.44%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Lowest Quarter Return

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Dec. 31, 2018

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(14.71%)

02.28 Select Portfolios: Group 7 Information Technology Sector Combo PRO-16 | Software and IT Services Portfolio | Return Before Taxes | Software and IT Services Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Software and IT Services Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return Before Taxes</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

38.87%

Past 5 years

rr_AverageAnnualReturnYear05

19.56%

Past 10 years

rr_AverageAnnualReturnYear10

19.08%

02.28 Select Portfolios: Group 7 Information Technology Sector Combo PRO-16 | Software and IT Services Portfolio | After Taxes on Distributions | Software and IT Services Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Software and IT Services Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

34.71%

Past 5 years

rr_AverageAnnualReturnYear05

17.43%

Past 10 years

rr_AverageAnnualReturnYear10

16.84%

02.28 Select Portfolios: Group 7 Information Technology Sector Combo PRO-16 | Software and IT Services Portfolio | After Taxes on Distributions and Sales | Software and IT Services Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Software and IT Services Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions and Sale of Fund Shares</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

25.44%

Past 5 years

rr_AverageAnnualReturnYear05

15.31%

Past 10 years

rr_AverageAnnualReturnYear10

15.37%

02.28 Select Portfolios: Group 7 Information Technology Sector Combo PRO-16 | Software and IT Services Portfolio | S&P 500® Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

31.49%

Past 5 years

rr_AverageAnnualReturnYear05

11.70%

Past 10 years

rr_AverageAnnualReturnYear10

13.56%

02.28 Select Portfolios: Group 7 Information Technology Sector Combo PRO-16 | Software and IT Services Portfolio | MSCI U.S. IMI Software & Services 25-50 Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

41.35%

Past 5 years

rr_AverageAnnualReturnYear05

20.04%

Past 10 years

rr_AverageAnnualReturnYear10

17.76%

[1] Differs from the ratios of expenses to average net assets in the Financial Highlights section of the prospectus because of acquired fund fees and expenses. For the period, acquired fund fees and expenses are less than 0.01% and are included in other expenses.

XML

Label

Element

Value

Risk/Return:

rr_RiskReturnAbstract

Registrant Name

dei_EntityRegistrantName

FIDELITY SELECT PORTFOLIOS

Prospectus Date

rr_ProspectusDate

Apr. 29, 2020

02.28 Select Portfolios: Group 7 Information Technology Sector Combo PRO-16 | Computers Portfolio

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: bold 12pt Arial, Helvetica, sans-serif;">Fund:<br/>Computers Portfolio</p>

Objective [Heading]

rr_ObjectiveHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks capital appreciation.

Expense [Heading]

rr_ExpenseHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

Shareholder Fees Caption [Text]

rr_ShareholderFeesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

(fees paid directly from your investment)

rr_ShareholderFeeOther

none

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

Portfolio Turnover [Text Block]

rr_PortfolioTurnoverTextBlock

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 116% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

116.00%

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Strategy [Heading]

rr_StrategyHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in research, design, development, manufacture, or distribution of products, processes, or services that relate to currently available or experimental hardware technology within the computer industry.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

Strategy Portfolio Concentration [Text]

rr_StrategyPortfolioConcentration

<font style="FONT-FAMILY: Times New Roman" size="3">Normally investing at least 80% of assets in securities of companies principally engaged in research, design, development, manufacture, or distribution of products, processes, or services that relate to currently available or experimental hardware technology within the computer industry.</font>

Risk [Heading]

rr_RiskHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets, particularly emerging markets, can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market. Emerging markets can be subject to greater social, economic, regulatory, and political uncertainties and can be extremely volatile.

• Geographic Concentration in Japan. Because the fund concentrates its investments in Japan, the fund's performance is expected to be closely tied to social, political, and economic conditions within Japan and to be more volatile than the performance of more geographically diversified funds.

• Computer Industry Concentration. The computer industry can be significantly affected by competitive pressures, changing domestic and international demand, research and development costs, availability and price of components, and product obsolescence.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

• High Portfolio Turnover. High portfolio turnover (more than 100%) may result in increased transaction costs and potentially higher capital gains or losses. The effects of higher than normal portfolio turnover may adversely affect the fund's performance.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

Risk Lose Money [Text]

rr_RiskLoseMoney

<font style="FONT-FAMILY: Times New Roman" size="3">You could lose money by investing in the fund.</font>

Risk Nondiversified Status [Text]

rr_RiskNondiversifiedStatus

<font style="FONT-FAMILY: Times New Roman" size="3">In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.</font>

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

<font style="FONT-FAMILY: Times New Roman" size="3">An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</font>

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

<font style="FONT-FAMILY: Times New Roman" size="3">The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time.</font>

Performance Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

<font style="FONT-FAMILY: Times New Roman" size="3">www.fidelity.com </font>

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

<font style="FONT-FAMILY: Times New Roman" size="3">Past performance (before and after taxes) is not an indication of future performance.</font>

Bar Chart [Heading]

rr_BarChartHeading

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	25.29%	March 31, 2012
Lowest Quarter Return	-19.07%	December 31, 2018
Year-to-Date Return	-14.95%	March 31, 2020

Performance Table Heading

rr_PerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

<font style="FONT-FAMILY: Times New Roman" size="3">After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes.</font>

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

<font style="FONT-FAMILY: Times New Roman" size="3">The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan).</font>

Performance Table Explanation after Tax Higher

rr_PerformanceTableExplanationAfterTaxHigher

<font style="FONT-FAMILY: Times New Roman" size="3">Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.</font>

Performance Table Narrative

rr_PerformanceTableNarrativeTextBlock

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

02.28 Select Portfolios: Group 7 Information Technology Sector Combo PRO-16 | Computers Portfolio | Computers Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Management fee

rr_ManagementFeesOverAssets

0.54%

Distribution and/or Service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

none

Other expenses

rr_OtherExpensesOverAssets

0.22%

Total annual operating expenses

rr_ExpensesOverAssets

0.76%

1 year

rr_ExpenseExampleYear01

$ 78

3 years

rr_ExpenseExampleYear03

243

5 years

rr_ExpenseExampleYear05

422

10 years

rr_ExpenseExampleYear10

$ 942

2010

rr_AnnualReturn2010

23.76%

2011

rr_AnnualReturn2011

(4.48%)

2012

rr_AnnualReturn2012

14.26%

2013

rr_AnnualReturn2013

31.09%

2014

rr_AnnualReturn2014

14.73%

2015

rr_AnnualReturn2015

(13.80%)

2016

rr_AnnualReturn2016

15.81%

2017

rr_AnnualReturn2017

33.74%

2018

rr_AnnualReturn2018

(5.88%)

2019

rr_AnnualReturn2019

40.04%

Year to Date Return, Label

rr_YearToDateReturnLabel

Year-to-Date Return

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Mar. 31, 2020

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

(14.95%)

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Highest Quarter Return

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Mar. 31, 2012

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

25.29%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Lowest Quarter Return

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Dec. 31, 2018

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(19.07%)

02.28 Select Portfolios: Group 7 Information Technology Sector Combo PRO-16 | Computers Portfolio | Return Before Taxes | Computers Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Computers Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return Before Taxes</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

40.04%

Past 5 years

rr_AverageAnnualReturnYear05

11.97%

Past 10 years

rr_AverageAnnualReturnYear10

13.59%

02.28 Select Portfolios: Group 7 Information Technology Sector Combo PRO-16 | Computers Portfolio | After Taxes on Distributions | Computers Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Computers Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

35.84%

Past 5 years

rr_AverageAnnualReturnYear05

9.12%

Past 10 years

rr_AverageAnnualReturnYear10

11.84%

02.28 Select Portfolios: Group 7 Information Technology Sector Combo PRO-16 | Computers Portfolio | After Taxes on Distributions and Sales | Computers Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Computers Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions and Sale of Fund Shares</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

25.94%

Past 5 years

rr_AverageAnnualReturnYear05

8.88%

Past 10 years

rr_AverageAnnualReturnYear10

10.95%

02.28 Select Portfolios: Group 7 Information Technology Sector Combo PRO-16 | Computers Portfolio | S&P 500® Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

31.49%

Past 5 years

rr_AverageAnnualReturnYear05

11.70%

Past 10 years

rr_AverageAnnualReturnYear10

13.56%

02.28 Select Portfolios: Group 7 Information Technology Sector Combo PRO-16 | Computers Portfolio | FactSet Computers & Peripherals Linked Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

38.75%

Past 5 years

rr_AverageAnnualReturnYear05

7.56%

Past 10 years

rr_AverageAnnualReturnYear10

10.78%

XML

Label

Element

Value

Risk/Return:

rr_RiskReturnAbstract

Registrant Name

dei_EntityRegistrantName

FIDELITY SELECT PORTFOLIOS

Prospectus Date

rr_ProspectusDate

Apr. 29, 2020

02.28 Select Portfolios: Group 1 Consumer Discretionary Sector Combo PRO-16 | Retailing Portfolio

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: bold 12pt Arial, Helvetica, sans-serif;">Fund:<br/>Retailing Portfolio</p>

Objective [Heading]

rr_ObjectiveHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks capital appreciation.

Expense [Heading]

rr_ExpenseHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

Shareholder Fees Caption [Text]

rr_ShareholderFeesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

(fees paid directly from your investment)

rr_ShareholderFeeOther

none

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

Portfolio Turnover [Text Block]

rr_PortfolioTurnoverTextBlock

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 17% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

17.00%

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Strategy [Heading]

rr_StrategyHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in merchandising finished goods and services primarily to individual consumers.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

Strategy Portfolio Concentration [Text]

rr_StrategyPortfolioConcentration

<font style="FONT-FAMILY: Times New Roman" size="3">Normally investing at least 80% of assets in securities of companies principally engaged in merchandising finished goods and services primarily to individual consumers.</font>

Risk [Heading]

rr_RiskHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Retail Industry Concentration. The retail industry can be significantly affected by consumer confidence and spending, intense competition, and changing consumer tastes.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

Risk Lose Money [Text]

rr_RiskLoseMoney

<font style="FONT-FAMILY: Times New Roman" size="3">You could lose money by investing in the fund.</font>

Risk Nondiversified Status [Text]

rr_RiskNondiversifiedStatus

<font style="FONT-FAMILY: Times New Roman" size="3">In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.</font>

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

<font style="FONT-FAMILY: Times New Roman" size="3">An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</font>

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

<font style="FONT-FAMILY: Times New Roman" size="3">The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time.</font>

Performance Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

<font style="FONT-FAMILY: Times New Roman" size="3">www.fidelity.com </font>

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

<font style="FONT-FAMILY: Times New Roman" size="3">Past performance (before and after taxes) is not an indication of future performance.</font>

Bar Chart [Heading]

rr_BarChartHeading

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	20.23%	March 31, 2012
Lowest Quarter Return	-17.67%	December 31, 2018
Year-to-Date Return	-17.69%	March 31, 2020

Performance Table Heading

rr_PerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

<font style="FONT-FAMILY: Times New Roman" size="3">After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes.</font>

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

<font style="FONT-FAMILY: Times New Roman" size="3">The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan).</font>

Performance Table Explanation after Tax Higher

rr_PerformanceTableExplanationAfterTaxHigher

<font style="FONT-FAMILY: Times New Roman" size="3">Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.</font>

Performance Table Narrative

rr_PerformanceTableNarrativeTextBlock

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

02.28 Select Portfolios: Group 1 Consumer Discretionary Sector Combo PRO-16 | Retailing Portfolio | Retailing Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Management fee

rr_ManagementFeesOverAssets

0.54%

Distribution and/or Service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

none

Other expenses

rr_OtherExpensesOverAssets

0.20%

Total annual operating expenses

rr_ExpensesOverAssets

0.74%

1 year

rr_ExpenseExampleYear01

$ 76

3 years

rr_ExpenseExampleYear03

237

5 years

rr_ExpenseExampleYear05

411

10 years

rr_ExpenseExampleYear10

$ 918

2010

rr_AnnualReturn2010

28.06%

2011

rr_AnnualReturn2011

3.36%

2012

rr_AnnualReturn2012

24.83%

2013

rr_AnnualReturn2013

43.93%

2014

rr_AnnualReturn2014

12.02%

2015

rr_AnnualReturn2015

18.41%

2016

rr_AnnualReturn2016

4.43%

2017

rr_AnnualReturn2017

25.82%

2018

rr_AnnualReturn2018

4.62%

2019

rr_AnnualReturn2019

26.32%

Year to Date Return, Label

rr_YearToDateReturnLabel

Year-to-Date Return

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Mar. 31, 2020

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

(17.69%)

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Highest Quarter Return

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Mar. 31, 2012

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

20.23%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Lowest Quarter Return

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Dec. 31, 2018

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(17.67%)

02.28 Select Portfolios: Group 1 Consumer Discretionary Sector Combo PRO-16 | Retailing Portfolio | Return Before Taxes | Retailing Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Retailing Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return Before Taxes</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

26.32%

Past 5 years

rr_AverageAnnualReturnYear05

15.51%

Past 10 years

rr_AverageAnnualReturnYear10

18.54%

02.28 Select Portfolios: Group 1 Consumer Discretionary Sector Combo PRO-16 | Retailing Portfolio | After Taxes on Distributions | Retailing Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Retailing Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

25.65%

Past 5 years

rr_AverageAnnualReturnYear05

15.00%

Past 10 years

rr_AverageAnnualReturnYear10

17.65%

02.28 Select Portfolios: Group 1 Consumer Discretionary Sector Combo PRO-16 | Retailing Portfolio | After Taxes on Distributions and Sales | Retailing Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Retailing Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions and Sale of Fund Shares</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

16.01%

Past 5 years

rr_AverageAnnualReturnYear05

12.43%

Past 10 years

rr_AverageAnnualReturnYear10

15.57%

02.28 Select Portfolios: Group 1 Consumer Discretionary Sector Combo PRO-16 | Retailing Portfolio | S&P 500® Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

31.49%

Past 5 years

rr_AverageAnnualReturnYear05

11.70%

Past 10 years

rr_AverageAnnualReturnYear10

13.56%

02.28 Select Portfolios: Group 1 Consumer Discretionary Sector Combo PRO-16 | Retailing Portfolio | MSCI U.S. IMI Retailing 25-50 Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

24.95%

Past 5 years

rr_AverageAnnualReturnYear05

15.59%

Past 10 years

rr_AverageAnnualReturnYear10

18.72%

XML

Total

02.28 Select Portfolios: Group 5 Health Care Sector Combo PRO-13 | Biotechnology Portfolio

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: bold 12pt Arial, Helvetica, sans-serif;">Fund:<br/>Biotechnology Portfolio</p>

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

The fund seeks capital appreciation.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

Shareholder Fees {- Biotechnology Portfolio}	02.28 Select Portfolios: Group 5 Health Care Sector Combo PRO-13 Biotechnology Portfolio USD ($)
(fees paid directly from your investment)	none

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Annual Operating Expenses {- Biotechnology Portfolio}	02.28 Select Portfolios: Group 5 Health Care Sector Combo PRO-13 Biotechnology Portfolio Biotechnology Portfolio-Default
Management fee	0.54%
Distribution and/or Service (12b-1) fees	none
Other expenses	0.18%
Total annual operating expenses	0.72%

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Expense Example {- Biotechnology Portfolio}	02.28 Select Portfolios: Group 5 Health Care Sector Combo PRO-13 Biotechnology Portfolio Biotechnology Portfolio-Default USD ($)
1 year	$ 74
3 years	230
5 years	401
10 years	$ 894

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 50% of the average value of its portfolio.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in the research, development, manufacture, and distribution of various biotechnological products, services, and processes and companies that benefit significantly from scientific and technological advances in biotechnology.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Biotechnology Industry Concentration. The biotechnology industry can be significantly affected by patent considerations, intense competition, rapid technological change and obsolescence, and government regulation, and revenue patterns can be erratic.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	26.57%	December 31, 2019
Lowest Quarter Return	-28.45%	March 31, 2016
Year-to-Date Return	-14.71%	March 31, 2020

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

Average Annual Total Returns{- Biotechnology Portfolio} - 02.28 Select Portfolios: Group 5 Health Care Sector Combo PRO-13 - Biotechnology Portfolio	Past 1 year	Past 5 years	Past 10 years
Biotechnology Portfolio-Default | Return Before Taxes	35.96%	6.12%	18.40%
Biotechnology Portfolio-Default | After Taxes on Distributions	33.19%	4.64%	17.16%
Biotechnology Portfolio-Default | After Taxes on Distributions and Sales	23.15%	4.60%	15.62%
S&P 500® Index(reflects no deduction for fees, expenses, or taxes)	31.49%	11.70%	13.56%
MSCI U.S. IMI Biotechnology 25-50 Index(reflects no deduction for fees, expenses, or taxes)	21.12%	6.33%	18.27%

XML

Label

Element

Value

Risk/Return:

rr_RiskReturnAbstract

Registrant Name

dei_EntityRegistrantName

FIDELITY SELECT PORTFOLIOS

Prospectus Date

rr_ProspectusDate

Apr. 29, 2020

02.28 Select Portfolios: Group 2 Consumer Staples Sector Retail PRO-11 | Consumer Staples Portfolio

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: normal 12pt Arial, Helvetica, sans-serif;"><b>Fund/Class</b>:<br/><b>Consumer Staples Portfolio</b>/Consumer Staples Portfolio</p>

Objective [Heading]

rr_ObjectiveHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks capital appreciation.

Expense [Heading]

rr_ExpenseHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

Shareholder Fees Caption [Text]

rr_ShareholderFeesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

(fees paid directly from your investment)

rr_ShareholderFeeOther

none

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

Portfolio Turnover [Text Block]

rr_PortfolioTurnoverTextBlock

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 40% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

40.00%

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Strategy [Heading]

rr_StrategyHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in the manufacture, sale, or distribution of consumer staples.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

Strategy Portfolio Concentration [Text]

rr_StrategyPortfolioConcentration

<font style="FONT-FAMILY: Times New Roman" size="3">Normally investing at least 80% of assets in securities of companies principally engaged in the manufacture, sale, or distribution of consumer staples.</font>

Risk [Heading]

rr_RiskHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Consumer Staples Industry Concentration. The consumer staples industries can be significantly affected by demographics and product trends, competitive pricing, food fads, marketing campaigns, environmental factors, government regulation, the performance of the overall economy, interest rates, consumer confidence, and the cost of commodities.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

Risk Lose Money [Text]

rr_RiskLoseMoney

<font style="FONT-FAMILY: Times New Roman" size="3">You could lose money by investing in the fund.</font>

Risk Nondiversified Status [Text]

rr_RiskNondiversifiedStatus

<font style="FONT-FAMILY: Times New Roman" size="3">In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.</font>

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

<font style="FONT-FAMILY: Times New Roman" size="3">An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</font>

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

<font style="FONT-FAMILY: Times New Roman" size="3">The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time.</font>

Performance Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

<font style="FONT-FAMILY: Times New Roman" size="3">www.fidelity.com </font>

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

<font style="FONT-FAMILY: Times New Roman" size="3">Past performance (before and after taxes) is not an indication of future performance.</font>

Bar Chart [Heading]

rr_BarChartHeading

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	17.22%	March 31, 2019
Lowest Quarter Return	-10.53%	December 31, 2018
Year-to-Date Return	-16.58%	March 31, 2020

Performance Table Heading

rr_PerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

<font style="FONT-FAMILY: Times New Roman" size="3">After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes.</font>

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

<font style="FONT-FAMILY: Times New Roman" size="3">The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan).</font>

Performance Table Explanation after Tax Higher

rr_PerformanceTableExplanationAfterTaxHigher

<font style="FONT-FAMILY: Times New Roman" size="3">Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.</font>

Performance Table Narrative

rr_PerformanceTableNarrativeTextBlock

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

02.28 Select Portfolios: Group 2 Consumer Staples Sector Retail PRO-11 | Consumer Staples Portfolio | Consumer Staples Portfolio

Risk/Return:

rr_RiskReturnAbstract

Management fee

rr_ManagementFeesOverAssets

0.54%

Distribution and/or Service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

none

Other expenses

rr_OtherExpensesOverAssets

0.21%

Total annual operating expenses

rr_ExpensesOverAssets

0.75%

1 year

rr_ExpenseExampleYear01

$ 77

3 years

rr_ExpenseExampleYear03

240

5 years

rr_ExpenseExampleYear05

417

10 years

rr_ExpenseExampleYear10

$ 930

2010

rr_AnnualReturn2010

15.20%

2011

rr_AnnualReturn2011

8.84%

2012

rr_AnnualReturn2012

15.39%

2013

rr_AnnualReturn2013

21.63%

2014

rr_AnnualReturn2014

14.91%

2015

rr_AnnualReturn2015

1.90%

2016

rr_AnnualReturn2016

3.07%

2017

rr_AnnualReturn2017

12.06%

2018

rr_AnnualReturn2018

(15.82%)

2019

rr_AnnualReturn2019

31.77%

Year to Date Return, Label

rr_YearToDateReturnLabel

Year-to-Date Return

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Mar. 31, 2020

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

(16.58%)

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Highest Quarter Return

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Mar. 31, 2019

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

17.22%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Lowest Quarter Return

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Dec. 31, 2018

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(10.53%)

02.28 Select Portfolios: Group 2 Consumer Staples Sector Retail PRO-11 | Consumer Staples Portfolio | Return Before Taxes | Consumer Staples Portfolio

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Consumer Staples Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return Before Taxes</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

31.77%

Past 5 years

rr_AverageAnnualReturnYear05

5.48%

Past 10 years

rr_AverageAnnualReturnYear10

10.20%

02.28 Select Portfolios: Group 2 Consumer Staples Sector Retail PRO-11 | Consumer Staples Portfolio | After Taxes on Distributions | Consumer Staples Portfolio

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Consumer Staples Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

30.92%

Past 5 years

rr_AverageAnnualReturnYear05

3.68%

Past 10 years

rr_AverageAnnualReturnYear10

8.75%

02.28 Select Portfolios: Group 2 Consumer Staples Sector Retail PRO-11 | Consumer Staples Portfolio | After Taxes on Distributions and Sales | Consumer Staples Portfolio

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Consumer Staples Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions and Sale of Fund Shares</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

19.41%

Past 5 years

rr_AverageAnnualReturnYear05

4.05%

Past 10 years

rr_AverageAnnualReturnYear10

8.21%

02.28 Select Portfolios: Group 2 Consumer Staples Sector Retail PRO-11 | Consumer Staples Portfolio | S&P 500® Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

31.49%

Past 5 years

rr_AverageAnnualReturnYear05

11.70%

Past 10 years

rr_AverageAnnualReturnYear10

13.56%

02.28 Select Portfolios: Group 2 Consumer Staples Sector Retail PRO-11 | Consumer Staples Portfolio | MSCI U.S. IMI Consumer Staples 25-50 Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

26.20%

Past 5 years

rr_AverageAnnualReturnYear05

8.03%

Past 10 years

rr_AverageAnnualReturnYear10

12.25%

XML

Label

Element

Value

Risk/Return:

rr_RiskReturnAbstract

Registrant Name

dei_EntityRegistrantName

FIDELITY SELECT PORTFOLIOS

Prospectus Date

rr_ProspectusDate

Apr. 29, 2020

02.28 Select Portfolios: Group 6 Industrials Sector Combo PRO-10 | Industrials Portfolio

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: bold 12pt Arial, Helvetica, sans-serif;">Fund:<br/>Industrials Portfolio</p>

Objective [Heading]

rr_ObjectiveHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks capital appreciation.

Expense [Heading]

rr_ExpenseHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

Shareholder Fees Caption [Text]

rr_ShareholderFeesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

(fees paid directly from your investment)

rr_ShareholderFeeOther

none

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

Portfolio Turnover [Text Block]

rr_PortfolioTurnoverTextBlock

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 143% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

143.00%

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Strategy [Heading]

rr_StrategyHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in the research, development, manufacture, distribution, supply, or sale of industrial products, services, or equipment.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

Strategy Portfolio Concentration [Text]

rr_StrategyPortfolioConcentration

<font style="FONT-FAMILY: Times New Roman" size="3">Normally investing at least 80% of assets in securities of companies principally engaged in the research, development, manufacture, distribution, supply, or sale of industrial products, services, or equipment.</font>

Risk [Heading]

rr_RiskHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Industrials Industry Concentration. Industrial industries can be significantly affected by general economic trends, changes in consumer sentiment and spending, commodity prices, legislation, government regulation and spending, import controls, worldwide competition, and liability for environmental damage, depletion of resources, and mandated expenditures for safety and pollution control.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

• High Portfolio Turnover. High portfolio turnover (more than 100%) may result in increased transaction costs and potentially higher capital gains or losses. The effects of higher than normal portfolio turnover may adversely affect the fund's performance.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

Risk Lose Money [Text]

rr_RiskLoseMoney

<font style="FONT-FAMILY: Times New Roman" size="3">You could lose money by investing in the fund.</font>

Risk Nondiversified Status [Text]

rr_RiskNondiversifiedStatus

<font style="FONT-FAMILY: Times New Roman" size="3">In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.</font>

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

<font style="FONT-FAMILY: Times New Roman" size="3">An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</font>

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

<font style="FONT-FAMILY: Times New Roman" size="3">The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time.</font>

Performance Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

<font style="FONT-FAMILY: Times New Roman" size="3">www.fidelity.com </font>

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

<font style="FONT-FAMILY: Times New Roman" size="3">Past performance (before and after taxes) is not an indication of future performance.</font>

Bar Chart [Heading]

rr_BarChartHeading

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	17.89%	March 31, 2019
Lowest Quarter Return	-22.42%	September 30, 2011
Year-to-Date Return	-28.64%	March 31, 2020

Performance Table Heading

rr_PerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

<font style="FONT-FAMILY: Times New Roman" size="3">After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes.</font>

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

<font style="FONT-FAMILY: Times New Roman" size="3">The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan).</font>

Performance Table Explanation after Tax Higher

rr_PerformanceTableExplanationAfterTaxHigher

<font style="FONT-FAMILY: Times New Roman" size="3">Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.</font>

Performance Table Narrative

rr_PerformanceTableNarrativeTextBlock

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

02.28 Select Portfolios: Group 6 Industrials Sector Combo PRO-10 | Industrials Portfolio | Industrials Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Management fee

rr_ManagementFeesOverAssets

0.54%

Distribution and/or Service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

none

Other expenses

rr_OtherExpensesOverAssets

0.22%

Total annual operating expenses

rr_ExpensesOverAssets

0.76%

1 year

rr_ExpenseExampleYear01

$ 78

3 years

rr_ExpenseExampleYear03

243

5 years

rr_ExpenseExampleYear05

422

10 years

rr_ExpenseExampleYear10

$ 942

2010

rr_AnnualReturn2010

31.08%

2011

rr_AnnualReturn2011

(4.88%)

2012

rr_AnnualReturn2012

19.60%

2013

rr_AnnualReturn2013

39.90%

2014

rr_AnnualReturn2014

5.81%

2015

rr_AnnualReturn2015

(1.97%)

2016

rr_AnnualReturn2016

15.53%

2017

rr_AnnualReturn2017

20.08%

2018

rr_AnnualReturn2018

(15.27%)

2019

rr_AnnualReturn2019

27.99%

Year to Date Return, Label

rr_YearToDateReturnLabel

Year-to-Date Return

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Mar. 31, 2020

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

(28.64%)

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Highest Quarter Return

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Mar. 31, 2019

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

17.89%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Lowest Quarter Return

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Sep. 30, 2011

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(22.42%)

02.28 Select Portfolios: Group 6 Industrials Sector Combo PRO-10 | Industrials Portfolio | Return Before Taxes | Industrials Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Industrials Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return Before Taxes</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

27.99%

Past 5 years

rr_AverageAnnualReturnYear05

8.08%

Past 10 years

rr_AverageAnnualReturnYear10

12.53%

02.28 Select Portfolios: Group 6 Industrials Sector Combo PRO-10 | Industrials Portfolio | After Taxes on Distributions | Industrials Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Industrials Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

26.77%

Past 5 years

rr_AverageAnnualReturnYear05

6.64%

Past 10 years

rr_AverageAnnualReturnYear10

11.20%

02.28 Select Portfolios: Group 6 Industrials Sector Combo PRO-10 | Industrials Portfolio | After Taxes on Distributions and Sales | Industrials Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Industrials Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions and Sale of Fund Shares</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

17.44%

Past 5 years

rr_AverageAnnualReturnYear05

6.16%

Past 10 years

rr_AverageAnnualReturnYear10

10.19%

02.28 Select Portfolios: Group 6 Industrials Sector Combo PRO-10 | Industrials Portfolio | S&P 500® Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

31.49%

Past 5 years

rr_AverageAnnualReturnYear05

11.70%

Past 10 years

rr_AverageAnnualReturnYear10

13.56%

02.28 Select Portfolios: Group 6 Industrials Sector Combo PRO-10 | Industrials Portfolio | MSCI U.S. IMI Industrials 25-50 Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

30.28%

Past 5 years

rr_AverageAnnualReturnYear05

9.65%

Past 10 years

rr_AverageAnnualReturnYear10

13.61%

XML

Total

02.28 Select Portfolios: Group 6 Industrials Sector Combo PRO-10 | Air Transportation Portfolio

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: bold 12pt Arial, Helvetica, sans-serif;">Fund:<br/>Air Transportation Portfolio</p>

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

The fund seeks capital appreciation.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

Shareholder Fees {- Air Transportation Portfolio}	02.28 Select Portfolios: Group 6 Industrials Sector Combo PRO-10 Air Transportation Portfolio USD ($)
(fees paid directly from your investment)	none

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Annual Operating Expenses {- Air Transportation Portfolio}	02.28 Select Portfolios: Group 6 Industrials Sector Combo PRO-10 Air Transportation Portfolio Air Transportation Portfolio-Default
Management fee	0.54%
Distribution and/or Service (12b-1) fees	none
Other expenses	0.27%
Total annual operating expenses	0.81%

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Expense Example {- Air Transportation Portfolio}	02.28 Select Portfolios: Group 6 Industrials Sector Combo PRO-10 Air Transportation Portfolio Air Transportation Portfolio-Default USD ($)
1 year	$ 83
3 years	259
5 years	450
10 years	$ 1,002

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 95% of the average value of its portfolio.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in the regional, national, and international movement of passengers, mail, and freight via aircraft.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Air Transportation Industry Concentration. The air transportation industry can be significantly affected by competition within the industry, domestic and foreign economies, government regulation, labor relations, the price of fuel, and geopolitical developments.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	21.51%	March 31, 2010
Lowest Quarter Return	-17.00%	December 31, 2018
Year-to-Date Return	-42.40%	March 31, 2020

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

Average Annual Total Returns{- Air Transportation Portfolio} - 02.28 Select Portfolios: Group 6 Industrials Sector Combo PRO-10 - Air Transportation Portfolio	Past 1 year	Past 5 years	Past 10 years
Air Transportation Portfolio-Default | Return Before Taxes	21.00%	7.63%	15.32%
Air Transportation Portfolio-Default | After Taxes on Distributions	18.51%	5.61%	13.84%
Air Transportation Portfolio-Default | After Taxes on Distributions and Sales	14.07%	5.68%	12.69%
S&P 500® Index(reflects no deduction for fees, expenses, or taxes)	31.49%	11.70%	13.56%
Nasdaq North America Air Transportation Linked Index(reflects no deduction for fees, expenses, or taxes)	24.19%	9.58%	15.51%

XML

Label

Element

Value

Risk/Return:

rr_RiskReturnAbstract

Registrant Name

dei_EntityRegistrantName

FIDELITY SELECT PORTFOLIOS

Prospectus Date

rr_ProspectusDate

Apr. 29, 2020

02.28 Select Portfolios: Group 5 Health Care Sector Combo PRO-13 | Medical Technology and Devices Portfolio

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: bold 12pt Arial, Helvetica, sans-serif;">Fund:<br/>Medical Technology and Devices Portfolio</p>

Objective [Heading]

rr_ObjectiveHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks capital appreciation.

Expense [Heading]

rr_ExpenseHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

Shareholder Fees Caption [Text]

rr_ShareholderFeesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

(fees paid directly from your investment)

rr_ShareholderFeeOther

none

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

Portfolio Turnover [Text Block]

rr_PortfolioTurnoverTextBlock

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 35% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

35.00%

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Strategy [Heading]

rr_StrategyHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in research, development, manufacture, distribution, supply, or sale of medical equipment and devices and related technologies, companies enabling drug discovery, and companies providing information technology services primarily to health care providers.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

Strategy Portfolio Concentration [Text]

rr_StrategyPortfolioConcentration

<font style="FONT-FAMILY: Times New Roman" size="3">Normally investing at least 80% of assets in securities of companies principally engaged in research, development, manufacture, distribution, supply, or sale of medical equipment and devices and related technologies, companies enabling drug discovery, and companies providing information technology services primarily to health care providers.</font>

Risk [Heading]

rr_RiskHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Medical Technology and Devices Industry Concentration. The medical technology and devices industry can be significantly affected by patent considerations, competition, technology, government regulation, and government reimbursement for medical expenses.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

Risk Lose Money [Text]

rr_RiskLoseMoney

<font style="FONT-FAMILY: Times New Roman" size="3">You could lose money by investing in the fund.</font>

Risk Nondiversified Status [Text]

rr_RiskNondiversifiedStatus

<font style="FONT-FAMILY: Times New Roman" size="3">In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.</font>

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

<font style="FONT-FAMILY: Times New Roman" size="3">An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</font>

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Prior to January 1, 2018, the fund was named Medical Equipment and Systems Portfolio, and the fund operated under certain different investment policies and compared its performance to a different additional index. The fund's historical performance may not represent its current investment policies. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

<font style="FONT-FAMILY: Times New Roman" size="3">The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time.</font>

Performance Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

<font style="FONT-FAMILY: Times New Roman" size="3">www.fidelity.com</font>

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

<font style="FONT-FAMILY: Times New Roman" size="3">Past performance (before and after taxes) is not an indication of future performance.</font>

Bar Chart [Heading]

rr_BarChartHeading

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	14.80%	June 30, 2016
Lowest Quarter Return	-14.68%	September 30, 2011
Year-to-Date Return	-14.04%	March 31, 2020

Performance Table Heading

rr_PerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

<font style="FONT-FAMILY: Times New Roman" size="3">After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes.</font>

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

<font style="FONT-FAMILY: Times New Roman" size="3">The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan).</font>

Performance Table Explanation after Tax Higher

rr_PerformanceTableExplanationAfterTaxHigher

<font style="FONT-FAMILY: Times New Roman" size="3">Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.</font>

Performance Table Narrative

rr_PerformanceTableNarrativeTextBlock

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

02.28 Select Portfolios: Group 5 Health Care Sector Combo PRO-13 | Medical Technology and Devices Portfolio | Medical Technology and Devices Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Management fee

rr_ManagementFeesOverAssets

0.54%

Distribution and/or Service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

none

Other expenses

rr_OtherExpensesOverAssets

0.17%

Total annual operating expenses

rr_ExpensesOverAssets

0.71%

1 year

rr_ExpenseExampleYear01

$ 73

3 years

rr_ExpenseExampleYear03

227

5 years

rr_ExpenseExampleYear05

395

10 years

rr_ExpenseExampleYear10

$ 883

2010

rr_AnnualReturn2010

12.71%

2011

rr_AnnualReturn2011

(3.42%)

2012

rr_AnnualReturn2012

15.62%

2013

rr_AnnualReturn2013

41.30%

2014

rr_AnnualReturn2014

26.70%

2015

rr_AnnualReturn2015

7.11%

2016

rr_AnnualReturn2016

8.68%

2017

rr_AnnualReturn2017

26.57%

2018

rr_AnnualReturn2018

16.20%

2019

rr_AnnualReturn2019

29.56%

Year to Date Return, Label

rr_YearToDateReturnLabel

Year-to-Date Return

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Mar. 31, 2020

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

(14.04%)

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Highest Quarter Return

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Jun. 30, 2016

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

14.80%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Lowest Quarter Return

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Sep. 30, 2011

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(14.68%)

02.28 Select Portfolios: Group 5 Health Care Sector Combo PRO-13 | Medical Technology and Devices Portfolio | Return Before Taxes | Medical Technology and Devices Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Medical Technology and Devices Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return Before Taxes</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

29.56%

Past 5 years

rr_AverageAnnualReturnYear05

17.28%

Past 10 years

rr_AverageAnnualReturnYear10

17.46%

02.28 Select Portfolios: Group 5 Health Care Sector Combo PRO-13 | Medical Technology and Devices Portfolio | After Taxes on Distributions | Medical Technology and Devices Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Medical Technology and Devices Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

29.03%

Past 5 years

rr_AverageAnnualReturnYear05

15.20%

Past 10 years

rr_AverageAnnualReturnYear10

15.48%

02.28 Select Portfolios: Group 5 Health Care Sector Combo PRO-13 | Medical Technology and Devices Portfolio | After Taxes on Distributions and Sales | Medical Technology and Devices Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Medical Technology and Devices Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions and Sale of Fund Shares</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

17.88%

Past 5 years

rr_AverageAnnualReturnYear05

13.25%

Past 10 years

rr_AverageAnnualReturnYear10

14.03%

02.28 Select Portfolios: Group 5 Health Care Sector Combo PRO-13 | Medical Technology and Devices Portfolio | S&P 500® Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

31.49%

Past 5 years

rr_AverageAnnualReturnYear05

11.70%

Past 10 years

rr_AverageAnnualReturnYear10

13.56%

02.28 Select Portfolios: Group 5 Health Care Sector Combo PRO-13 | Medical Technology and Devices Portfolio | MSCI U.S. IMI Custom Health Care Technology and Equipment 25/50 Linked Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

31.04%

Past 5 years

rr_AverageAnnualReturnYear05

17.90%

Past 10 years

rr_AverageAnnualReturnYear10

16.22%

XML

Total

02.28 Select Portfolios: Group 5 Health Care Sector Combo PRO-13 | Medical Technology and Devices Portfolio

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: bold 12pt Arial, Helvetica, sans-serif;">Fund:<br/>Medical Technology and Devices Portfolio</p>

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

The fund seeks capital appreciation.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

Shareholder Fees {- Medical Technology and Devices Portfolio}	02.28 Select Portfolios: Group 5 Health Care Sector Combo PRO-13 Medical Technology and Devices Portfolio USD ($)
(fees paid directly from your investment)	none

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Annual Operating Expenses {- Medical Technology and Devices Portfolio}	02.28 Select Portfolios: Group 5 Health Care Sector Combo PRO-13 Medical Technology and Devices Portfolio Medical Technology and Devices Portfolio-Default
Management fee	0.54%
Distribution and/or Service (12b-1) fees	none
Other expenses	0.17%
Total annual operating expenses	0.71%

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Expense Example {- Medical Technology and Devices Portfolio}	02.28 Select Portfolios: Group 5 Health Care Sector Combo PRO-13 Medical Technology and Devices Portfolio Medical Technology and Devices Portfolio-Default USD ($)
1 year	$ 73
3 years	227
5 years	395
10 years	$ 883

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 35% of the average value of its portfolio.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in research, development, manufacture, distribution, supply, or sale of medical equipment and devices and related technologies, companies enabling drug discovery, and companies providing information technology services primarily to health care providers.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Medical Technology and Devices Industry Concentration. The medical technology and devices industry can be significantly affected by patent considerations, competition, technology, government regulation, and government reimbursement for medical expenses.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Prior to January 1, 2018, the fund was named Medical Equipment and Systems Portfolio, and the fund operated under certain different investment policies and compared its performance to a different additional index. The fund's historical performance may not represent its current investment policies. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	14.80%	June 30, 2016
Lowest Quarter Return	-14.68%	September 30, 2011
Year-to-Date Return	-14.04%	March 31, 2020

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

Average Annual Total Returns{- Medical Technology and Devices Portfolio} - 02.28 Select Portfolios: Group 5 Health Care Sector Combo PRO-13 - Medical Technology and Devices Portfolio	Past 1 year	Past 5 years	Past 10 years
Medical Technology and Devices Portfolio-Default | Return Before Taxes	29.56%	17.28%	17.46%
Medical Technology and Devices Portfolio-Default | After Taxes on Distributions	29.03%	15.20%	15.48%
Medical Technology and Devices Portfolio-Default | After Taxes on Distributions and Sales	17.88%	13.25%	14.03%
S&P 500® Index(reflects no deduction for fees, expenses, or taxes)	31.49%	11.70%	13.56%
MSCI U.S. IMI Custom Health Care Technology and Equipment 25/50 Linked Index(reflects no deduction for fees, expenses, or taxes)	31.04%	17.90%	16.22%

XML

Total

02.28 Select Portfolios: Group 4 Financials Sector Combo PRO-15 | Banking Portfolio

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: bold 12pt Arial, Helvetica, sans-serif;">Fund:<br/>Banking Portfolio</p>

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

The fund seeks capital appreciation.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

Shareholder Fees {- Banking Portfolio}	02.28 Select Portfolios: Group 4 Financials Sector Combo PRO-15 Banking Portfolio USD ($)
(fees paid directly from your investment)	none

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Annual Operating Expenses {- Banking Portfolio}	02.28 Select Portfolios: Group 4 Financials Sector Combo PRO-15 Banking Portfolio Banking Portfolio-Default
Management fee	0.54%
Distribution and/or Service (12b-1) fees	none
Other expenses	0.23%
Total annual operating expenses	0.77%

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Expense Example {- Banking Portfolio}	02.28 Select Portfolios: Group 4 Financials Sector Combo PRO-15 Banking Portfolio Banking Portfolio-Default USD ($)
1 year	$ 79
3 years	246
5 years	428
10 years	$ 954

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 31% of the average value of its portfolio.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in banking.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Banking Industry Concentration. The banking industry can be significantly affected by legislation, regulation, competition and by changes in general economic conditions and interest rates.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	27.24%	December 31, 2016
Lowest Quarter Return	-22.08%	September 30, 2011
Year-to-Date Return	-43.51%	March 31, 2020

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

Average Annual Total Returns{- Banking Portfolio} - 02.28 Select Portfolios: Group 4 Financials Sector Combo PRO-15 - Banking Portfolio	Past 1 year	Past 5 years	Past 10 years
Banking Portfolio-Default | Return Before Taxes	35.59%	9.77%	11.91%
Banking Portfolio-Default | After Taxes on Distributions	33.68%	7.72%	10.62%
Banking Portfolio-Default | After Taxes on Distributions and Sales	22.31%	7.42%	9.69%
S&P 500® Index(reflects no deduction for fees, expenses, or taxes)	31.49%	11.70%	13.56%
MSCI US IMI Banks 5% Capped Linked Index(reflects no deduction for fees, expenses, or taxes)	30.77%	10.67%	12.41%

XML

Label

Element

Value

Risk/Return:

rr_RiskReturnAbstract

Registrant Name

dei_EntityRegistrantName

FIDELITY SELECT PORTFOLIOS

Prospectus Date

rr_ProspectusDate

Apr. 29, 2020

02.28 Select Portfolios: Group 8 Materials Sector Retail Combo PRO-15 | Materials Portfolio

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: normal 12pt Arial, Helvetica, sans-serif;"><b>Fund/Class</b>:<br/><b>Materials Portfolio</b>/Materials Portfolio</p>

Objective [Heading]

rr_ObjectiveHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks capital appreciation.

Expense [Heading]

rr_ExpenseHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

Shareholder Fees Caption [Text]

rr_ShareholderFeesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

(fees paid directly from your investment)

rr_ShareholderFeeOther

none

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

Portfolio Turnover [Text Block]

rr_PortfolioTurnoverTextBlock

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 69% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

69.00%

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Strategy [Heading]

rr_StrategyHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in the manufacture, mining, processing, or distribution of raw materials and intermediate goods.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

Strategy Portfolio Concentration [Text]

rr_StrategyPortfolioConcentration

<font style="FONT-FAMILY: Times New Roman" size="3">Normally investing at least 80% of assets in securities of companies principally engaged in the manufacture, mining, processing, or distribution of raw materials and intermediate goods.</font>

Risk [Heading]

rr_RiskHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Materials Industry Concentration. The materials industries can be significantly affected by the level and volatility of commodity prices, the exchange value of the dollar, import and export controls, worldwide competition, liability for environmental damage, depletion of resources, and mandated expenditures for safety and pollution control.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

Risk Lose Money [Text]

rr_RiskLoseMoney

<font style="FONT-FAMILY: Times New Roman" size="3">You could lose money by investing in the fund.</font>

Risk Nondiversified Status [Text]

rr_RiskNondiversifiedStatus

<font style="FONT-FAMILY: Times New Roman" size="3">In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.</font>

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

<font style="FONT-FAMILY: Times New Roman" size="3">An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</font>

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

<font style="FONT-FAMILY: Times New Roman" size="3">The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time.</font>

Performance Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

<font style="FONT-FAMILY: Times New Roman" size="3">www.fidelity.com </font>

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

<font style="FONT-FAMILY: Times New Roman" size="3">Past performance (before and after taxes) is not an indication of future performance.</font>

Bar Chart [Heading]

rr_BarChartHeading

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	20.90%	December 31, 2010
Lowest Quarter Return	-25.30%	September 30, 2011
Year-to-Date Return	-26.30%	March 31, 2020

Performance Table Heading

rr_PerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

<font style="FONT-FAMILY: Times New Roman" size="3">After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes.</font>

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

<font style="FONT-FAMILY: Times New Roman" size="3">The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan).</font>

Performance Table Explanation after Tax Higher

rr_PerformanceTableExplanationAfterTaxHigher

<font style="FONT-FAMILY: Times New Roman" size="3">Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.</font>

Performance Table Narrative

rr_PerformanceTableNarrativeTextBlock

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

02.28 Select Portfolios: Group 8 Materials Sector Retail Combo PRO-15 | Materials Portfolio | Materials Portfolio

Risk/Return:

rr_RiskReturnAbstract

Management fee

rr_ManagementFeesOverAssets

0.53%

Distribution and/or Service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

none

Other expenses

rr_OtherExpensesOverAssets

0.27%

Total annual operating expenses

rr_ExpensesOverAssets

0.80%

1 year

rr_ExpenseExampleYear01

$ 82

3 years

rr_ExpenseExampleYear03

255

5 years

rr_ExpenseExampleYear05

444

10 years

rr_ExpenseExampleYear10

$ 990

2010

rr_AnnualReturn2010

28.09%

2011

rr_AnnualReturn2011

(8.20%)

2012

rr_AnnualReturn2012

20.17%

2013

rr_AnnualReturn2013

21.90%

2014

rr_AnnualReturn2014

(0.06%)

2015

rr_AnnualReturn2015

(8.68%)

2016

rr_AnnualReturn2016

11.99%

2017

rr_AnnualReturn2017

26.22%

2018

rr_AnnualReturn2018

(23.65%)

2019

rr_AnnualReturn2019

12.40%

Year to Date Return, Label

rr_YearToDateReturnLabel

Year-to-Date Return

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Mar. 31, 2020

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

(26.30%)

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Highest Quarter Return

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Dec. 31, 2010

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

20.90%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Lowest Quarter Return

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Sep. 30, 2011

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(25.30%)

02.28 Select Portfolios: Group 8 Materials Sector Retail Combo PRO-15 | Materials Portfolio | Return Before Taxes | Materials Portfolio

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Materials Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return Before Taxes</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

12.40%

Past 5 years

rr_AverageAnnualReturnYear05

2.07%

Past 10 years

rr_AverageAnnualReturnYear10

6.67%

02.28 Select Portfolios: Group 8 Materials Sector Retail Combo PRO-15 | Materials Portfolio | After Taxes on Distributions | Materials Portfolio

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Materials Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

12.08%

Past 5 years

rr_AverageAnnualReturnYear05

1.07%

Past 10 years

rr_AverageAnnualReturnYear10

5.74%

02.28 Select Portfolios: Group 8 Materials Sector Retail Combo PRO-15 | Materials Portfolio | After Taxes on Distributions and Sales | Materials Portfolio

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Materials Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions and Sale of Fund Shares</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

7.57%

Past 5 years

rr_AverageAnnualReturnYear05

1.59%

Past 10 years

rr_AverageAnnualReturnYear10

5.38%

02.28 Select Portfolios: Group 8 Materials Sector Retail Combo PRO-15 | Materials Portfolio | S&P 500® Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

31.49%

Past 5 years

rr_AverageAnnualReturnYear05

11.70%

Past 10 years

rr_AverageAnnualReturnYear10

13.56%

02.28 Select Portfolios: Group 8 Materials Sector Retail Combo PRO-15 | Materials Portfolio | MSCI U.S. IMI Materials 25-50 Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

23.80%

Past 5 years

rr_AverageAnnualReturnYear05

6.70%

Past 10 years

rr_AverageAnnualReturnYear10

9.30%

XML

Label

Element

Value

Risk/Return:

rr_RiskReturnAbstract

Registrant Name

dei_EntityRegistrantName

FIDELITY SELECT PORTFOLIOS

Prospectus Date

rr_ProspectusDate

Apr. 29, 2020

02.28 Select Portfolios: Group 8 Materials Sector Retail Combo PRO-15 | Chemicals Portfolio

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: bold 12pt Arial, Helvetica, sans-serif;">Fund:<br/>Chemicals Portfolio</p>

Objective [Heading]

rr_ObjectiveHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks capital appreciation.

Expense [Heading]

rr_ExpenseHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

Shareholder Fees Caption [Text]

rr_ShareholderFeesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

(fees paid directly from your investment)

rr_ShareholderFeeOther

none

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

Portfolio Turnover [Text Block]

rr_PortfolioTurnoverTextBlock

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 77% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

77.00%

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Strategy [Heading]

rr_StrategyHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in the research, development, manufacture, or marketing of products or services related to the chemical process industries.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

Strategy Portfolio Concentration [Text]

rr_StrategyPortfolioConcentration

<font style="FONT-FAMILY: Times New Roman" size="3">Normally investing at least 80% of assets in securities of companies principally engaged in the research, development, manufacture, or marketing of products or services related to the chemical process industries.</font>

Risk [Heading]

rr_RiskHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Chemicals Industry Concentration. The chemicals industry can be significantly affected by intense competition, product obsolescence, raw materials prices, and government regulation, and can be subject to risks associated with the production, handling, and disposal of hazardous components.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

Risk Lose Money [Text]

rr_RiskLoseMoney

<font style="FONT-FAMILY: Times New Roman" size="3">You could lose money by investing in the fund.</font>

Risk Nondiversified Status [Text]

rr_RiskNondiversifiedStatus

<font style="FONT-FAMILY: Times New Roman" size="3">In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.</font>

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

<font style="FONT-FAMILY: Times New Roman" size="3">An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</font>

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

<font style="FONT-FAMILY: Times New Roman" size="3">The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time.</font>

Performance Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

<font style="FONT-FAMILY: Times New Roman" size="3">www.fidelity.com </font>

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

<font style="FONT-FAMILY: Times New Roman" size="3">Past performance (before and after taxes) is not an indication of future performance.</font>

Bar Chart [Heading]

rr_BarChartHeading

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	22.72%	September 30, 2010
Lowest Quarter Return	-24.12%	September 30, 2011
Year-to-Date Return	-29.08%	March 31, 2020

Performance Table Heading

rr_PerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

<font style="FONT-FAMILY: Times New Roman" size="3">After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes.</font>

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

<font style="FONT-FAMILY: Times New Roman" size="3">The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan).</font>

Performance Table Explanation after Tax Higher

rr_PerformanceTableExplanationAfterTaxHigher

<font style="FONT-FAMILY: Times New Roman" size="3">Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.</font>

Performance Table Narrative

rr_PerformanceTableNarrativeTextBlock

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

02.28 Select Portfolios: Group 8 Materials Sector Retail Combo PRO-15 | Chemicals Portfolio | Chemicals Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Management fee

rr_ManagementFeesOverAssets

0.53%

Distribution and/or Service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

none

Other expenses

rr_OtherExpensesOverAssets

0.25%

Total annual operating expenses

rr_ExpensesOverAssets

0.78%

1 year

rr_ExpenseExampleYear01

$ 80

3 years

rr_ExpenseExampleYear03

249

5 years

rr_ExpenseExampleYear05

433

10 years

rr_ExpenseExampleYear10

$ 966

2010

rr_AnnualReturn2010

30.73%

2011

rr_AnnualReturn2011

0.29%

2012

rr_AnnualReturn2012

30.01%

2013

rr_AnnualReturn2013

29.86%

2014

rr_AnnualReturn2014

4.56%

2015

rr_AnnualReturn2015

(5.10%)

2016

rr_AnnualReturn2016

17.98%

2017

rr_AnnualReturn2017

31.75%

2018

rr_AnnualReturn2018

(22.19%)

2019

rr_AnnualReturn2019

8.24%

Year to Date Return, Label

rr_YearToDateReturnLabel

Year-to-Date Return

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Mar. 31, 2020

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

(29.08%)

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Highest Quarter Return

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Sep. 30, 2010

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

22.72%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Lowest Quarter Return

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Sep. 30, 2011

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(24.12%)

02.28 Select Portfolios: Group 8 Materials Sector Retail Combo PRO-15 | Chemicals Portfolio | Return Before Taxes | Chemicals Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Chemicals Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return Before Taxes</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

8.24%

Past 5 years

rr_AverageAnnualReturnYear05

4.44%

Past 10 years

rr_AverageAnnualReturnYear10

11.14%

02.28 Select Portfolios: Group 8 Materials Sector Retail Combo PRO-15 | Chemicals Portfolio | After Taxes on Distributions | Chemicals Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Chemicals Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

6.59%

Past 5 years

rr_AverageAnnualReturnYear05

2.39%

Past 10 years

rr_AverageAnnualReturnYear10

9.62%

02.28 Select Portfolios: Group 8 Materials Sector Retail Combo PRO-15 | Chemicals Portfolio | After Taxes on Distributions and Sales | Chemicals Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Chemicals Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions and Sale of Fund Shares</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

6.13%

Past 5 years

rr_AverageAnnualReturnYear05

3.25%

Past 10 years

rr_AverageAnnualReturnYear10

9.03%

02.28 Select Portfolios: Group 8 Materials Sector Retail Combo PRO-15 | Chemicals Portfolio | S&P 500® Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

31.49%

Past 5 years

rr_AverageAnnualReturnYear05

11.70%

Past 10 years

rr_AverageAnnualReturnYear10

13.56%

02.28 Select Portfolios: Group 8 Materials Sector Retail Combo PRO-15 | Chemicals Portfolio | MSCI U.S. IMI Chemicals 25-50 Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

19.69%

Past 5 years

rr_AverageAnnualReturnYear05

7.20%

Past 10 years

rr_AverageAnnualReturnYear10

12.46%

XML

Total

02.28 Select Portfolios: Group 8 Materials Sector Retail Combo PRO-15 | Materials Portfolio

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: normal 12pt Arial, Helvetica, sans-serif;"><b>Fund/Class</b>:<br/><b>Materials Portfolio</b>/Materials Portfolio</p>

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

The fund seeks capital appreciation.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

Shareholder Fees {- Materials Portfolio}	02.28 Select Portfolios: Group 8 Materials Sector Retail Combo PRO-15 Materials Portfolio USD ($)
(fees paid directly from your investment)	none

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Annual Operating Expenses {- Materials Portfolio}	02.28 Select Portfolios: Group 8 Materials Sector Retail Combo PRO-15 Materials Portfolio Materials Portfolio
Management fee	0.53%
Distribution and/or Service (12b-1) fees	none
Other expenses	0.27%
Total annual operating expenses	0.80%

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Expense Example {- Materials Portfolio}	02.28 Select Portfolios: Group 8 Materials Sector Retail Combo PRO-15 Materials Portfolio Materials Portfolio USD ($)
1 year	$ 82
3 years	255
5 years	444
10 years	$ 990

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 69% of the average value of its portfolio.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in the manufacture, mining, processing, or distribution of raw materials and intermediate goods.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Materials Industry Concentration. The materials industries can be significantly affected by the level and volatility of commodity prices, the exchange value of the dollar, import and export controls, worldwide competition, liability for environmental damage, depletion of resources, and mandated expenditures for safety and pollution control.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	20.90%	December 31, 2010
Lowest Quarter Return	-25.30%	September 30, 2011
Year-to-Date Return	-26.30%	March 31, 2020

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

Average Annual Total Returns{- Materials Portfolio} - 02.28 Select Portfolios: Group 8 Materials Sector Retail Combo PRO-15 - Materials Portfolio	Past 1 year	Past 5 years	Past 10 years
Materials Portfolio | Return Before Taxes	12.40%	2.07%	6.67%
Materials Portfolio | After Taxes on Distributions	12.08%	1.07%	5.74%
Materials Portfolio | After Taxes on Distributions and Sales	7.57%	1.59%	5.38%
S&P 500® Index(reflects no deduction for fees, expenses, or taxes)	31.49%	11.70%	13.56%
MSCI U.S. IMI Materials 25-50 Index(reflects no deduction for fees, expenses, or taxes)	23.80%	6.70%	9.30%

XML

Label

Element

Value

Risk/Return:

rr_RiskReturnAbstract

Registrant Name

dei_EntityRegistrantName

FIDELITY SELECT PORTFOLIOS

Prospectus Date

rr_ProspectusDate

Apr. 29, 2020

02.28 Select Portfolios: Group 3 Energy Sector Combo PRO-13 | Natural Gas Portfolio

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: bold 12pt Arial, Helvetica, sans-serif;">Fund:<br/>Natural Gas Portfolio</p>

Objective [Heading]

rr_ObjectiveHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks capital appreciation.

Expense [Heading]

rr_ExpenseHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

Shareholder Fees Caption [Text]

rr_ShareholderFeesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

(fees paid directly from your investment)

rr_ShareholderFeeOther

none

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

Portfolio Turnover [Text Block]

rr_PortfolioTurnoverTextBlock

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 87% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

87.00%

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Strategy [Heading]

rr_StrategyHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in the production, transmission, and distribution of natural gas, and involved in the exploration of potential natural gas sources, as well as those companies that provide services and equipment to natural gas producers, refineries, cogeneration facilities, converters, and distributors.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

Strategy Portfolio Concentration [Text]

rr_StrategyPortfolioConcentration

<font style="FONT-FAMILY: Times New Roman" size="3">Normally investing at least 80% of assets in securities of companies principally engaged in the production, transmission, and distribution of natural gas, and involved in the exploration of potential natural gas sources, as well as those companies that provide services and equipment to natural gas producers, refineries, cogeneration facilities, converters, and distributors.</font>

Risk [Heading]

rr_RiskHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Natural Gas Industry Concentration. The natural gas industry is subject to changes in price and supply of energy sources and can be significantly affected by events relating to international politics, energy conservation, the success of energy source exploration projects, and tax and other government regulations.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

Risk Lose Money [Text]

rr_RiskLoseMoney

<font style="FONT-FAMILY: Times New Roman" size="3">You could lose money by investing in the fund.</font>

Risk Nondiversified Status [Text]

rr_RiskNondiversifiedStatus

<font style="FONT-FAMILY: Times New Roman" size="3">In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.</font>

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

<font style="FONT-FAMILY: Times New Roman" size="3">An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</font>

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

<font style="FONT-FAMILY: Times New Roman" size="3">The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time.</font>

Performance Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

<font style="FONT-FAMILY: Times New Roman" size="3">www.fidelity.com </font>

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

<font style="FONT-FAMILY: Times New Roman" size="3">Past performance (before and after taxes) is not an indication of future performance.</font>

Bar Chart [Heading]

rr_BarChartHeading

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	18.16%	June 30, 2016
Lowest Quarter Return	-30.78%	December 31, 2018
Year-to-Date Return	-55.51%	March 31, 2020

Performance Table Heading

rr_PerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

<font style="FONT-FAMILY: Times New Roman" size="3">After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes.</font>

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

<font style="FONT-FAMILY: Times New Roman" size="3">The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan).</font>

Performance Table Explanation after Tax Higher

rr_PerformanceTableExplanationAfterTaxHigher

<font style="FONT-FAMILY: Times New Roman" size="3">Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.</font>

Performance Table Narrative

rr_PerformanceTableNarrativeTextBlock

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

02.28 Select Portfolios: Group 3 Energy Sector Combo PRO-13 | Natural Gas Portfolio | Natural Gas Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Management fee

rr_ManagementFeesOverAssets

0.53%

Distribution and/or Service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

none

Other expenses

rr_OtherExpensesOverAssets

0.40%

Total annual operating expenses

rr_ExpensesOverAssets

0.93%

1 year

rr_ExpenseExampleYear01

$ 95

3 years

rr_ExpenseExampleYear03

296

5 years

rr_ExpenseExampleYear05

515

10 years

rr_ExpenseExampleYear10

$ 1,143

2010

rr_AnnualReturn2010

6.43%

2011

rr_AnnualReturn2011

(7.67%)

2012

rr_AnnualReturn2012

2.44%

2013

rr_AnnualReturn2013

24.66%

2014

rr_AnnualReturn2014

(13.29%)

2015

rr_AnnualReturn2015

(36.82%)

2016

rr_AnnualReturn2016

48.46%

2017

rr_AnnualReturn2017

(15.64%)

2018

rr_AnnualReturn2018

(25.35%)

2019

rr_AnnualReturn2019

3.58%

Year to Date Return, Label

rr_YearToDateReturnLabel

Year-to-Date Return

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Mar. 31, 2020

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

(55.51%)

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Highest Quarter Return

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Jun. 30, 2016

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

18.16%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Lowest Quarter Return

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Dec. 31, 2018

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(30.78%)

02.28 Select Portfolios: Group 3 Energy Sector Combo PRO-13 | Natural Gas Portfolio | Return Before Taxes | Natural Gas Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Natural Gas Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return Before Taxes</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

3.58%

Past 5 years

rr_AverageAnnualReturnYear05

(9.36%)

Past 10 years

rr_AverageAnnualReturnYear10

(3.99%)

02.28 Select Portfolios: Group 3 Energy Sector Combo PRO-13 | Natural Gas Portfolio | After Taxes on Distributions | Natural Gas Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Natural Gas Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

3.32%

Past 5 years

rr_AverageAnnualReturnYear05

(9.74%)

Past 10 years

rr_AverageAnnualReturnYear10

(4.30%)

02.28 Select Portfolios: Group 3 Energy Sector Combo PRO-13 | Natural Gas Portfolio | After Taxes on Distributions and Sales | Natural Gas Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Natural Gas Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions and Sale of Fund Shares</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

2.30%

Past 5 years

rr_AverageAnnualReturnYear05

(6.76%)

Past 10 years

rr_AverageAnnualReturnYear10

(2.80%)

02.28 Select Portfolios: Group 3 Energy Sector Combo PRO-13 | Natural Gas Portfolio | S&P 500® Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

31.49%

Past 5 years

rr_AverageAnnualReturnYear05

11.70%

Past 10 years

rr_AverageAnnualReturnYear10

13.56%

02.28 Select Portfolios: Group 3 Energy Sector Combo PRO-13 | Natural Gas Portfolio | FactSet Natural Gas Linked Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

11.75%

Past 5 years

rr_AverageAnnualReturnYear05

(5.48%)

Past 10 years

rr_AverageAnnualReturnYear10

0.22%

XML

Label

Element

Value

Risk/Return:

rr_RiskReturnAbstract

Registrant Name

dei_EntityRegistrantName

FIDELITY SELECT PORTFOLIOS

Prospectus Date

rr_ProspectusDate

Apr. 29, 2020

02.28 Select Portfolios: Group 4 Financials Sector Combo PRO-15 | Insurance Portfolio

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: bold 12pt Arial, Helvetica, sans-serif;">Fund:<br/>Insurance Portfolio</p>

Objective [Heading]

rr_ObjectiveHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks capital appreciation.

Expense [Heading]

rr_ExpenseHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

Shareholder Fees Caption [Text]

rr_ShareholderFeesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

(fees paid directly from your investment)

rr_ShareholderFeeOther

none

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

Portfolio Turnover [Text Block]

rr_PortfolioTurnoverTextBlock

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 28% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

28.00%

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Strategy [Heading]

rr_StrategyHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in underwriting, reinsuring, selling, distributing, or placing of property and casualty, life, or health insurance.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

Strategy Portfolio Concentration [Text]

rr_StrategyPortfolioConcentration

<font style="FONT-FAMILY: Times New Roman" size="3">Normally investing at least 80% of assets in securities of companies principally engaged in underwriting, reinsuring, selling, distributing, or placing of property and casualty, life, or health insurance.</font>

Risk [Heading]

rr_RiskHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Insurance Industry Concentration. The insurance industry is subject to extensive government regulation and can be significantly affected by interest rates, general economic conditions, and price and marketing competition. Different segments of the industry can be significantly affected by natural disasters, mortality and morbidity rates, and environmental clean-up.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

Risk Lose Money [Text]

rr_RiskLoseMoney

<font style="FONT-FAMILY: Times New Roman" size="3">You could lose money by investing in the fund.</font>

Risk Nondiversified Status [Text]

rr_RiskNondiversifiedStatus

<font style="FONT-FAMILY: Times New Roman" size="3">In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.</font>

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

<font style="FONT-FAMILY: Times New Roman" size="3">An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</font>

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

<font style="FONT-FAMILY: Times New Roman" size="3">The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time.</font>

Performance Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

<font style="FONT-FAMILY: Times New Roman" size="3">www.fidelity.com </font>

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

<font style="FONT-FAMILY: Times New Roman" size="3">Past performance (before and after taxes) is not an indication of future performance.</font>

Bar Chart [Heading]

rr_BarChartHeading

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	14.69%	March 31, 2013
Lowest Quarter Return	-17.60%	September 30, 2011
Year-to-Date Return	-29.18%	March 31, 2020

Performance Table Heading

rr_PerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

<font style="FONT-FAMILY: Times New Roman" size="3">After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes.</font>

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

<font style="FONT-FAMILY: Times New Roman" size="3">The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan).</font>

Performance Table Explanation after Tax Higher

rr_PerformanceTableExplanationAfterTaxHigher

<font style="FONT-FAMILY: Times New Roman" size="3">Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.</font>

Performance Table Narrative

rr_PerformanceTableNarrativeTextBlock

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

02.28 Select Portfolios: Group 4 Financials Sector Combo PRO-15 | Insurance Portfolio | Insurance Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Management fee

rr_ManagementFeesOverAssets

0.53%

Distribution and/or Service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

none

Other expenses

rr_OtherExpensesOverAssets

0.28%

Total annual operating expenses

rr_ExpensesOverAssets

0.81%

1 year

rr_ExpenseExampleYear01

$ 83

3 years

rr_ExpenseExampleYear03

259

5 years

rr_ExpenseExampleYear05

450

10 years

rr_ExpenseExampleYear10

$ 1,002

2010

rr_AnnualReturn2010

20.13%

2011

rr_AnnualReturn2011

(5.16%)

2012

rr_AnnualReturn2012

19.67%

2013

rr_AnnualReturn2013

43.80%

2014

rr_AnnualReturn2014

9.90%

2015

rr_AnnualReturn2015

3.47%

2016

rr_AnnualReturn2016

18.17%

2017

rr_AnnualReturn2017

15.38%

2018

rr_AnnualReturn2018

(11.24%)

2019

rr_AnnualReturn2019

30.03%

Year to Date Return, Label

rr_YearToDateReturnLabel

Year-to-Date Return

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Mar. 31, 2020

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

(29.18%)

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Highest Quarter Return

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Mar. 31, 2013

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

14.69%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Lowest Quarter Return

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Sep. 30, 2011

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(17.60%)

02.28 Select Portfolios: Group 4 Financials Sector Combo PRO-15 | Insurance Portfolio | Return Before Taxes | Insurance Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Insurance Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return Before Taxes</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

30.03%

Past 5 years

rr_AverageAnnualReturnYear05

10.24%

Past 10 years

rr_AverageAnnualReturnYear10

13.37%

02.28 Select Portfolios: Group 4 Financials Sector Combo PRO-15 | Insurance Portfolio | After Taxes on Distributions | Insurance Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Insurance Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

27.86%

Past 5 years

rr_AverageAnnualReturnYear05

7.60%

Past 10 years

rr_AverageAnnualReturnYear10

11.36%

02.28 Select Portfolios: Group 4 Financials Sector Combo PRO-15 | Insurance Portfolio | After Taxes on Distributions and Sales | Insurance Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Insurance Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions and Sale of Fund Shares</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

19.13%

Past 5 years

rr_AverageAnnualReturnYear05

7.74%

Past 10 years

rr_AverageAnnualReturnYear10

10.75%

02.28 Select Portfolios: Group 4 Financials Sector Combo PRO-15 | Insurance Portfolio | S&P 500® Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

31.49%

Past 5 years

rr_AverageAnnualReturnYear05

11.70%

Past 10 years

rr_AverageAnnualReturnYear10

13.56%

02.28 Select Portfolios: Group 4 Financials Sector Combo PRO-15 | Insurance Portfolio | MSCI U.S. IMI Insurance 25-50 Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

28.44%

Past 5 years

rr_AverageAnnualReturnYear05

10.78%

Past 10 years

rr_AverageAnnualReturnYear10

13.45%

XML

Total

02.28 Select Portfolios: Group 7 Information Technology Sector Combo PRO-16 | IT Services Portfolio

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: bold 12pt Arial, Helvetica, sans-serif;">Fund:<br/>IT Services Portfolio</p>

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

The fund seeks capital appreciation.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

Shareholder Fees {- IT Services Portfolio}	02.28 Select Portfolios: Group 7 Information Technology Sector Combo PRO-16 IT Services Portfolio USD ($)
(fees paid directly from your investment)	none

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Annual Operating Expenses {- IT Services Portfolio}	02.28 Select Portfolios: Group 7 Information Technology Sector Combo PRO-16 IT Services Portfolio IT Services Portfolio-Default
Management fee	0.54%
Distribution and/or Service (12b-1) fees	none
Other expenses	0.19%
Total annual operating expenses	0.73%

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Expense Example {- IT Services Portfolio}	02.28 Select Portfolios: Group 7 Information Technology Sector Combo PRO-16 IT Services Portfolio IT Services Portfolio-Default USD ($)
1 year	$ 75
3 years	233
5 years	406
10 years	$ 906

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 24% of the average value of its portfolio.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in providing information technology services.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• IT Services Industry Concentration. The IT services industry can be significantly affected by competitive pressures, such as technological developments, fixed-rate pricing, and the ability to attract and retain skilled employees, and the success of companies in the industry is subject to continued demand for IT services.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	25.49%	March 31, 2019
Lowest Quarter Return	-17.05%	December 31, 2018
Year-to-Date Return	-16.20%	March 31, 2020

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

Average Annual Total Returns{- IT Services Portfolio} - 02.28 Select Portfolios: Group 7 Information Technology Sector Combo PRO-16 - IT Services Portfolio	Past 1 year	Past 5 years	Past 10 years
IT Services Portfolio-Default | Return Before Taxes	42.23%	18.81%	18.78%
IT Services Portfolio-Default | After Taxes on Distributions	41.45%	17.98%	17.98%
IT Services Portfolio-Default | After Taxes on Distributions and Sales	25.54%	15.10%	15.87%
S&P 500® Index(reflects no deduction for fees, expenses, or taxes)	31.49%	11.70%	13.56%
MSCI U.S. IMI Information Technology Services 25-50 Index(reflects no deduction for fees, expenses, or taxes)	41.01%	17.66%	17.13%

XML

Total

02.28 Select Portfolios: Group 5 Health Care Sector Combo PRO-13 | Pharmaceuticals Portfolio

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: bold 12pt Arial, Helvetica, sans-serif;">Fund:<br/>Pharmaceuticals Portfolio</p>

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

The fund seeks capital appreciation.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

Shareholder Fees {- Pharmaceuticals Portfolio}	02.28 Select Portfolios: Group 5 Health Care Sector Combo PRO-13 Pharmaceuticals Portfolio USD ($)
(fees paid directly from your investment)	none

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Annual Operating Expenses {- Pharmaceuticals Portfolio}	02.28 Select Portfolios: Group 5 Health Care Sector Combo PRO-13 Pharmaceuticals Portfolio Pharmaceuticals Portfolio-Default
Management fee	0.54%
Distribution and/or Service (12b-1) fees	none
Other expenses	0.24%
Total annual operating expenses	0.78%

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Expense Example {- Pharmaceuticals Portfolio}	02.28 Select Portfolios: Group 5 Health Care Sector Combo PRO-13 Pharmaceuticals Portfolio Pharmaceuticals Portfolio-Default USD ($)
1 year	$ 80
3 years	249
5 years	433
10 years	$ 966

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 52% of the average value of its portfolio.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in companies engaged in the research, development, manufacture, sale, or distribution of pharmaceuticals and drugs of all types.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Pharmaceuticals Industry Concentration. The pharmaceuticals industry can be significantly affected by government approval of products and services, government regulation and reimbursement rates, patent expirations, and intense competition.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	17.28%	December 31, 2019
Lowest Quarter Return	-11.62%	March 31, 2016
Year-to-Date Return	-10.00%	March 31, 2020

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

Average Annual Total Returns{- Pharmaceuticals Portfolio} - 02.28 Select Portfolios: Group 5 Health Care Sector Combo PRO-13 - Pharmaceuticals Portfolio	Past 1 year	Past 5 years	Past 10 years
Pharmaceuticals Portfolio-Default | Return Before Taxes	31.63%	6.91%	13.96%
Pharmaceuticals Portfolio-Default | After Taxes on Distributions	28.96%	5.62%	12.51%
Pharmaceuticals Portfolio-Default | After Taxes on Distributions and Sales	20.28%	5.19%	11.37%
S&P 500® Index(reflects no deduction for fees, expenses, or taxes)	31.49%	11.70%	13.56%
MSCI North America IMI + ADR Custom Pharmaceuticals 25/50 Linked Index(reflects no deduction for fees, expenses, or taxes)	18.56%	4.80%	12.24%

XML

Total

02.28 Select Portfolios: Fidelity Advisor Consumer Staples Fund - AMCIZ PRO-13 | Consumer Staples Portfolio

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: normal 12pt Arial, Helvetica, sans-serif;"><b>Fund/Class</b>:<br/><b>Consumer Staples Portfolio</b>/Fidelity Advisor® Consumer Staples Fund A, M, C, I, Z</p>

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

The fund seeks capital appreciation.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund. In addition to the fees and expenses described below, your broker may also require you to pay brokerage commissions on purchases and sales of certain share classes of the fund.

You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $50,000 in the fund or certain other Fidelity^® funds. More information about these and other discounts is available from your investment professional and in the "Fund Distribution" section beginning on page 27 of the prospectus. Different intermediaries may provide additional waivers or reductions of the sales charge. Please see “Sales Charge Waiver Policies Applied by Certain Intermediaries” in the “Appendix” section of the prospectus.

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(fees paid directly from your investment)</p>

Shareholder Fees {- Consumer Staples Portfolio} - 02.28 Select Portfolios: Fidelity Advisor Consumer Staples Fund - AMCIZ PRO-13 - Consumer Staples Portfolio	Fidelity Advisor Consumer Staples Fund: Class A		Fidelity Advisor Consumer Staples Fund: Class M		Fidelity Advisor Consumer Staples Fund: Class C		Fidelity Advisor Consumer Staples Fund: Class I	Fidelity Advisor Consumer Staples Fund: Class Z
Maximum sales charge (load) on purchases (as a % of offering price)	5.75%		3.50%		none		none	none
Maximum contingent deferred sales charge (as a % of the lesser of original purchase price or redemption proceeds)	none	[1]	none	[1]	1.00%	[2]	none	none

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Annual Operating Expenses {- Consumer Staples Portfolio} - 02.28 Select Portfolios: Fidelity Advisor Consumer Staples Fund - AMCIZ PRO-13 - Consumer Staples Portfolio	Fidelity Advisor Consumer Staples Fund: Class A	Fidelity Advisor Consumer Staples Fund: Class M	Fidelity Advisor Consumer Staples Fund: Class C	Fidelity Advisor Consumer Staples Fund: Class I	Fidelity Advisor Consumer Staples Fund: Class Z
Management fee	0.54%	0.54%	0.54%	0.54%	0.54%
Distribution and/or Service (12b-1) fees	0.25%	0.50%	1.00%	none	none
Other expenses	0.25%	0.27%	0.25%	0.22%	0.09%
Total annual operating expenses	1.04%	1.31%	1.79%	0.76%	0.63%

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated and if you hold your shares:

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Expense Example {- Consumer Staples Portfolio} - 02.28 Select Portfolios: Fidelity Advisor Consumer Staples Fund - AMCIZ PRO-13 - Consumer Staples Portfolio - USD ($)	Fidelity Advisor Consumer Staples Fund: Class A	Fidelity Advisor Consumer Staples Fund: Class M	Fidelity Advisor Consumer Staples Fund: Class C	Fidelity Advisor Consumer Staples Fund: Class I	Fidelity Advisor Consumer Staples Fund: Class Z
1 year	$ 675	$ 479	$ 282	$ 78	$ 64
3 years	887	751	563	243	202
5 years	1,116	1,043	970	422	351
10 years	$ 1,773	$ 1,874	$ 2,105	$ 942	$ 786

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Hold Shares</p>

Expense Example, No Redemption {- Consumer Staples Portfolio} - 02.28 Select Portfolios: Fidelity Advisor Consumer Staples Fund - AMCIZ PRO-13 - Consumer Staples Portfolio - USD ($)	Fidelity Advisor Consumer Staples Fund: Class A	Fidelity Advisor Consumer Staples Fund: Class M	Fidelity Advisor Consumer Staples Fund: Class C	Fidelity Advisor Consumer Staples Fund: Class I	Fidelity Advisor Consumer Staples Fund: Class Z
1 Year	$ 675	$ 479	$ 182	$ 78	$ 64
3 Years	887	751	563	243	202
5 Years	1,116	1,043	970	422	351
10 Years	$ 1,773	$ 1,874	$ 2,105	$ 942	$ 786

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 40% of the average value of its portfolio.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in the manufacture, sale, or distribution of consumer staples.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Consumer Staples Industry Concentration. The consumer staples industries can be significantly affected by demographics and product trends, competitive pricing, food fads, marketing campaigns, environmental factors, government regulation, the performance of the overall economy, interest rates, consumer confidence, and the cost of commodities.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit institutional.fidelity.com for more recent performance information.

The returns in the bar chart do not reflect any applicable sales charges; if sales charges were reflected, returns would be lower than those shown.

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

During the periods shown in the chart for Class A:	Returns	Quarter ended
Highest Quarter Return	17.13%	March 31, 2019
Lowest Quarter Return	-10.60%	December 31, 2018
Year-to-Date Return	-16.65%	March 31, 2020

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

Unlike the returns in the bar chart, the returns in the table reflect the maximum applicable sales charges. After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. After-tax returns for Class A are shown in the table below and after-tax returns for other classes will vary. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

Average Annual Total Returns{- Consumer Staples Portfolio} - 02.28 Select Portfolios: Fidelity Advisor Consumer Staples Fund - AMCIZ PRO-13 - Consumer Staples Portfolio	Past 1 year	Past 5 years	Past 10 years	Since Inception	[1]	Inception Date
Fidelity Advisor Consumer Staples Fund: Class A | Return Before Taxes	23.83%	3.94%	9.24%
Fidelity Advisor Consumer Staples Fund: Class A | After Taxes on Distributions	23.09%	2.22%	7.86%
Fidelity Advisor Consumer Staples Fund: Class A | After Taxes on Distributions and Sales	14.63%	2.85%	7.39%
Fidelity Advisor Consumer Staples Fund: Class M | Return Before Taxes	26.45%	4.15%	9.20%
Fidelity Advisor Consumer Staples Fund: Class C | Return Before Taxes	29.42%	4.40%	9.08%
Fidelity Advisor Consumer Staples Fund: Class I | Return Before Taxes	31.75%	5.47%	10.18%
Fidelity Advisor Consumer Staples Fund: Class Z | Return Before Taxes	31.93%			14.11%		Oct. 02, 2018
S&P 500® Index(reflects no deduction for fees, expenses, or taxes)	31.49%	11.70%	13.56%
MSCI U.S. IMI Consumer Staples 25-50 Index(reflects no deduction for fees, expenses, or taxes)	26.20%	8.03%	12.25%

02.28 Select Portfolios: Fidelity Advisor Consumer Staples Fund - AMCIZ PRO-13 | Consumer Staples Portfolio | Fidelity Advisor Consumer Staples Fund: Class A

Class A and Class M purchases of $1 million or more will not be subject to a front-end sales charge. Such Class A and Class M purchases may be subject, upon redemption, to a contingent deferred sales charge (CDSC) of 1.00% or 0.25%, respectively.

02.28 Select Portfolios: Fidelity Advisor Consumer Staples Fund - AMCIZ PRO-13 | Consumer Staples Portfolio | Fidelity Advisor Consumer Staples Fund: Class M

Class A and Class M purchases of $1 million or more will not be subject to a front-end sales charge. Such Class A and Class M purchases may be subject, upon redemption, to a contingent deferred sales charge (CDSC) of 1.00% or 0.25%, respectively.

02.28 Select Portfolios: Fidelity Advisor Consumer Staples Fund - AMCIZ PRO-13 | Consumer Staples Portfolio | Fidelity Advisor Consumer Staples Fund: Class C

On Class C shares redeemed less than one year after purchase.

[1] Class A and Class M purchases of $1 million or more will not be subject to a front-end sales charge. Such Class A and Class M purchases may be subject, upon redemption, to a contingent deferred sales charge (CDSC) of 1.00% or 0.25%, respectively.

[2] On Class C shares redeemed less than one year after purchase.

[1] Since inception October 2, 2018.

XML

Label

Element

Value

Risk/Return:

rr_RiskReturnAbstract

Registrant Name

dei_EntityRegistrantName

FIDELITY SELECT PORTFOLIOS

Prospectus Date

rr_ProspectusDate

Apr. 29, 2020

02.28 Select Portfolios: Group 6 Industrials Sector Combo PRO-10 | Transportation Portfolio

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: bold 12pt Arial, Helvetica, sans-serif;">Fund:<br/>Transportation Portfolio</p>

Objective [Heading]

rr_ObjectiveHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks capital appreciation.

Expense [Heading]

rr_ExpenseHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

Shareholder Fees Caption [Text]

rr_ShareholderFeesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

(fees paid directly from your investment)

rr_ShareholderFeeOther

none

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

Portfolio Turnover [Text Block]

rr_PortfolioTurnoverTextBlock

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 78% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

78.00%

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Strategy [Heading]

rr_StrategyHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

• Normally investing primarily in common stocks.

• Investing in domestic and foreign issuers.

• Normally investing at least 80% of assets in securities of companies principally engaged in providing transportation services or companies principally engaged in the design, manufacture, distribution, or sale of transportation equipment.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

Strategy Portfolio Concentration [Text]

rr_StrategyPortfolioConcentration

<font style="FONT-FAMILY: Times New Roman" size="3">Normally investing at least 80% of assets in securities of companies principally engaged in providing transportation services or companies principally engaged in the design, manufacture, distribution, or sale of transportation equipment.</font>

Risk [Heading]

rr_RiskHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Transportation Industry Concentration. The transportation industry can be significantly affected by changes in the economy, fuel prices, labor relations, insurance costs, and government regulation.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

Risk Lose Money [Text]

rr_RiskLoseMoney

<font style="FONT-FAMILY: Times New Roman" size="3">You could lose money by investing in the fund.</font>

Risk Nondiversified Status [Text]

rr_RiskNondiversifiedStatus

<font style="FONT-FAMILY: Times New Roman" size="3">In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.</font>

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

<font style="FONT-FAMILY: Times New Roman" size="3">An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</font>

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

<font style="FONT-FAMILY: Times New Roman" size="3">The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time.</font>

Performance Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

<font style="FONT-FAMILY: Times New Roman" size="3">www.fidelity.com </font>

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

<font style="FONT-FAMILY: Times New Roman" size="3">Past performance (before and after taxes) is not an indication of future performance.</font>

Bar Chart [Heading]

rr_BarChartHeading

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	20.72%	March 31, 2010
Lowest Quarter Return	-21.74%	September 30, 2011
Year-to-Date Return	-29.06%	March 31, 2020

Performance Table Heading

rr_PerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

<font style="FONT-FAMILY: Times New Roman" size="3">After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes.</font>

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

<font style="FONT-FAMILY: Times New Roman" size="3">The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan).</font>

Performance Table Explanation after Tax Higher

rr_PerformanceTableExplanationAfterTaxHigher

<font style="FONT-FAMILY: Times New Roman" size="3">Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.</font>

Performance Table Narrative

rr_PerformanceTableNarrativeTextBlock

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

02.28 Select Portfolios: Group 6 Industrials Sector Combo PRO-10 | Transportation Portfolio | Transportation Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Management fee

rr_ManagementFeesOverAssets

0.53%

Distribution and/or Service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

none

Other expenses

rr_OtherExpensesOverAssets

0.26%

Total annual operating expenses

rr_ExpensesOverAssets

0.79%

1 year

rr_ExpenseExampleYear01

$ 81

3 years

rr_ExpenseExampleYear03

252

5 years

rr_ExpenseExampleYear05

439

10 years

rr_ExpenseExampleYear10

$ 978

2010

rr_AnnualReturn2010

41.30%

2011

rr_AnnualReturn2011

(5.28%)

2012

rr_AnnualReturn2012

11.10%

2013

rr_AnnualReturn2013

48.35%

2014

rr_AnnualReturn2014

34.01%

2015

rr_AnnualReturn2015

(18.51%)

2016

rr_AnnualReturn2016

25.90%

2017

rr_AnnualReturn2017

22.20%

2018

rr_AnnualReturn2018

(10.93%)

2019

rr_AnnualReturn2019

18.39%

Year to Date Return, Label

rr_YearToDateReturnLabel

Year-to-Date Return

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Mar. 31, 2020

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

(29.06%)

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Highest Quarter Return

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Mar. 31, 2010

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

20.72%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Lowest Quarter Return

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Sep. 30, 2011

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(21.74%)

02.28 Select Portfolios: Group 6 Industrials Sector Combo PRO-10 | Transportation Portfolio | Return Before Taxes | Transportation Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Transportation Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return Before Taxes</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

18.39%

Past 5 years

rr_AverageAnnualReturnYear05

5.74%

Past 10 years

rr_AverageAnnualReturnYear10

14.60%

02.28 Select Portfolios: Group 6 Industrials Sector Combo PRO-10 | Transportation Portfolio | After Taxes on Distributions | Transportation Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Transportation Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

17.30%

Past 5 years

rr_AverageAnnualReturnYear05

4.32%

Past 10 years

rr_AverageAnnualReturnYear10

13.42%

02.28 Select Portfolios: Group 6 Industrials Sector Combo PRO-10 | Transportation Portfolio | After Taxes on Distributions and Sales | Transportation Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Transportation Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions and Sale of Fund Shares</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

11.66%

Past 5 years

rr_AverageAnnualReturnYear05

4.29%

Past 10 years

rr_AverageAnnualReturnYear10

12.11%

02.28 Select Portfolios: Group 6 Industrials Sector Combo PRO-10 | Transportation Portfolio | S&P 500® Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

31.49%

Past 5 years

rr_AverageAnnualReturnYear05

11.70%

Past 10 years

rr_AverageAnnualReturnYear10

13.56%

02.28 Select Portfolios: Group 6 Industrials Sector Combo PRO-10 | Transportation Portfolio | MSCI U.S. IMI Transportation 25-50 Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

22.79%

Past 5 years

rr_AverageAnnualReturnYear05

6.15%

Past 10 years

rr_AverageAnnualReturnYear10

14.21%

XML

Label

Element

Value

Risk/Return:

rr_RiskReturnAbstract

Registrant Name

dei_EntityRegistrantName

FIDELITY SELECT PORTFOLIOS

Prospectus Date

rr_ProspectusDate

Apr. 29, 2020

02.28 Select Portfolios: Group 1 Consumer Discretionary Sector Combo PRO-16 | Consumer Discretionary Portfolio

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: bold 12pt Arial, Helvetica, sans-serif;">Fund:<br/>Consumer Discretionary Portfolio</p>

Objective [Heading]

rr_ObjectiveHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks capital appreciation.

Expense [Heading]

rr_ExpenseHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

Shareholder Fees Caption [Text]

rr_ShareholderFeesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

(fees paid directly from your investment)

rr_ShareholderFeeOther

none

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

Portfolio Turnover [Text Block]

rr_PortfolioTurnoverTextBlock

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 41% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

41.00%

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Strategy [Heading]

rr_StrategyHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in the manufacture and distribution of consumer discretionary products and services.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

Strategy Portfolio Concentration [Text]

rr_StrategyPortfolioConcentration

<font style="FONT-FAMILY: Times New Roman" size="3">Normally investing at least 80% of assets in securities of companies principally engaged in the manufacture and distribution of consumer discretionary products and services.</font>

Risk [Heading]

rr_RiskHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Consumer Discretionary Industry Concentration. The consumer discretionary industries can be significantly affected by the performance of the overall economy, interest rates, competition, consumer confidence and spending, and changes in demographics and consumer tastes.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

Risk Lose Money [Text]

rr_RiskLoseMoney

<font style="FONT-FAMILY: Times New Roman" size="3">You could lose money by investing in the fund.</font>

Risk Nondiversified Status [Text]

rr_RiskNondiversifiedStatus

<font style="FONT-FAMILY: Times New Roman" size="3">In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.</font>

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

<font style="FONT-FAMILY: Times New Roman" size="3">An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</font>

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

<font style="FONT-FAMILY: Times New Roman" size="3">The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time.</font>

Performance Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

<font style="FONT-FAMILY: Times New Roman" size="3">www.fidelity.com </font>

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

<font style="FONT-FAMILY: Times New Roman" size="3">Past performance (before and after taxes) is not an indication of future performance.</font>

Bar Chart [Heading]

rr_BarChartHeading

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	17.82%	March 31, 2012
Lowest Quarter Return	-15.84%	December 31, 2018
Year-to-Date Return	-21.62%	March 31, 2020

Performance Table Heading

rr_PerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

<font style="FONT-FAMILY: Times New Roman" size="3">After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes.</font>

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

<font style="FONT-FAMILY: Times New Roman" size="3">The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan).</font>

Performance Table Explanation after Tax Higher

rr_PerformanceTableExplanationAfterTaxHigher

<font style="FONT-FAMILY: Times New Roman" size="3">Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.</font>

Performance Table Narrative

rr_PerformanceTableNarrativeTextBlock

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

02.28 Select Portfolios: Group 1 Consumer Discretionary Sector Combo PRO-16 | Consumer Discretionary Portfolio | Consumer Discretionary Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Management fee

rr_ManagementFeesOverAssets

0.54%

Distribution and/or Service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

none

Other expenses

rr_OtherExpensesOverAssets

0.22%

Total annual operating expenses

rr_ExpensesOverAssets

0.76%

1 year

rr_ExpenseExampleYear01

$ 78

3 years

rr_ExpenseExampleYear03

243

5 years

rr_ExpenseExampleYear05

422

10 years

rr_ExpenseExampleYear10

$ 942

2010

rr_AnnualReturn2010

31.24%

2011

rr_AnnualReturn2011

(1.66%)

2012

rr_AnnualReturn2012

21.12%

2013

rr_AnnualReturn2013

41.03%

2014

rr_AnnualReturn2014

10.21%

2015

rr_AnnualReturn2015

5.43%

2016

rr_AnnualReturn2016

4.35%

2017

rr_AnnualReturn2017

22.08%

2018

rr_AnnualReturn2018

(0.94%)

2019

rr_AnnualReturn2019

27.04%

Year to Date Return, Label

rr_YearToDateReturnLabel

Year-to-Date Return

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Mar. 31, 2020

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

(21.62%)

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Highest Quarter Return

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Mar. 31, 2012

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

17.82%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Lowest Quarter Return

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Dec. 31, 2018

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(15.84%)

02.28 Select Portfolios: Group 1 Consumer Discretionary Sector Combo PRO-16 | Consumer Discretionary Portfolio | Return Before Taxes | Consumer Discretionary Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Consumer Discretionary Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return Before Taxes</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

27.04%

Past 5 years

rr_AverageAnnualReturnYear05

11.07%

Past 10 years

rr_AverageAnnualReturnYear10

15.17%

02.28 Select Portfolios: Group 1 Consumer Discretionary Sector Combo PRO-16 | Consumer Discretionary Portfolio | After Taxes on Distributions | Consumer Discretionary Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Consumer Discretionary Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

26.35%

Past 5 years

rr_AverageAnnualReturnYear05

10.33%

Past 10 years

rr_AverageAnnualReturnYear10

13.96%

02.28 Select Portfolios: Group 1 Consumer Discretionary Sector Combo PRO-16 | Consumer Discretionary Portfolio | After Taxes on Distributions and Sales | Consumer Discretionary Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Consumer Discretionary Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions and Sale of Fund Shares</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

16.45%

Past 5 years

rr_AverageAnnualReturnYear05

8.67%

Past 10 years

rr_AverageAnnualReturnYear10

12.41%

02.28 Select Portfolios: Group 1 Consumer Discretionary Sector Combo PRO-16 | Consumer Discretionary Portfolio | S&P 500® Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

31.49%

Past 5 years

rr_AverageAnnualReturnYear05

11.70%

Past 10 years

rr_AverageAnnualReturnYear10

13.56%

02.28 Select Portfolios: Group 1 Consumer Discretionary Sector Combo PRO-16 | Consumer Discretionary Portfolio | MSCI U.S. IMI Consumer Discretionary 25-50 Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

27.65%

Past 5 years

rr_AverageAnnualReturnYear05

12.09%

Past 10 years

rr_AverageAnnualReturnYear10

16.80%

XML

Total

02.28 Select Portfolios: Group 1 Consumer Discretionary Sector Combo PRO-16 | Retailing Portfolio

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: bold 12pt Arial, Helvetica, sans-serif;">Fund:<br/>Retailing Portfolio</p>

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

The fund seeks capital appreciation.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

Shareholder Fees {- Retailing Portfolio}	02.28 Select Portfolios: Group 1 Consumer Discretionary Sector Combo PRO-16 Retailing Portfolio USD ($)
(fees paid directly from your investment)	none

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Annual Operating Expenses {- Retailing Portfolio}	02.28 Select Portfolios: Group 1 Consumer Discretionary Sector Combo PRO-16 Retailing Portfolio Retailing Portfolio-Default
Management fee	0.54%
Distribution and/or Service (12b-1) fees	none
Other expenses	0.20%
Total annual operating expenses	0.74%

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Expense Example {- Retailing Portfolio}	02.28 Select Portfolios: Group 1 Consumer Discretionary Sector Combo PRO-16 Retailing Portfolio Retailing Portfolio-Default USD ($)
1 year	$ 76
3 years	237
5 years	411
10 years	$ 918

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 17% of the average value of its portfolio.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in merchandising finished goods and services primarily to individual consumers.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Retail Industry Concentration. The retail industry can be significantly affected by consumer confidence and spending, intense competition, and changing consumer tastes.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	20.23%	March 31, 2012
Lowest Quarter Return	-17.67%	December 31, 2018
Year-to-Date Return	-17.69%	March 31, 2020

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

Average Annual Total Returns{- Retailing Portfolio} - 02.28 Select Portfolios: Group 1 Consumer Discretionary Sector Combo PRO-16 - Retailing Portfolio	Past 1 year	Past 5 years	Past 10 years
Retailing Portfolio-Default | Return Before Taxes	26.32%	15.51%	18.54%
Retailing Portfolio-Default | After Taxes on Distributions	25.65%	15.00%	17.65%
Retailing Portfolio-Default | After Taxes on Distributions and Sales	16.01%	12.43%	15.57%
S&P 500® Index(reflects no deduction for fees, expenses, or taxes)	31.49%	11.70%	13.56%
MSCI U.S. IMI Retailing 25-50 Index(reflects no deduction for fees, expenses, or taxes)	24.95%	15.59%	18.72%

XML

Label

Element

Value

Risk/Return:

rr_RiskReturnAbstract

Registrant Name

dei_EntityRegistrantName

FIDELITY SELECT PORTFOLIOS

Prospectus Date

rr_ProspectusDate

Apr. 29, 2020

02.28 Select Portfolios: Group 6 Industrials Sector Combo PRO-10 | Defense and Aerospace Portfolio

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: bold 12pt Arial, Helvetica, sans-serif;">Fund:<br/>Defense and Aerospace Portfolio</p>

Objective [Heading]

rr_ObjectiveHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks capital appreciation.

Expense [Heading]

rr_ExpenseHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

Shareholder Fees Caption [Text]

rr_ShareholderFeesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

(fees paid directly from your investment)

rr_ShareholderFeeOther

none

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

Portfolio Turnover [Text Block]

rr_PortfolioTurnoverTextBlock

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 40% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

40.00%

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Strategy [Heading]

rr_StrategyHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in the research, manufacture, or sale of products or services related to the defense or aerospace industries.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

Strategy Portfolio Concentration [Text]

rr_StrategyPortfolioConcentration

<font style="FONT-FAMILY: Times New Roman" size="3">Normally investing at least 80% of assets in securities of companies principally engaged in the research, manufacture, or sale of products or services related to the defense or aerospace industries.</font>

Risk [Heading]

rr_RiskHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Defense and Aerospace Industry Concentration. The defense and aerospace industry can be significantly affected by government defense and aerospace regulation and spending policies.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

Risk Lose Money [Text]

rr_RiskLoseMoney

<font style="FONT-FAMILY: Times New Roman" size="3">You could lose money by investing in the fund.</font>

Risk Nondiversified Status [Text]

rr_RiskNondiversifiedStatus

<font style="FONT-FAMILY: Times New Roman" size="3">In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.</font>

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

<font style="FONT-FAMILY: Times New Roman" size="3">An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</font>

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

<font style="FONT-FAMILY: Times New Roman" size="3">The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time.</font>

Performance Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

<font style="FONT-FAMILY: Times New Roman" size="3">www.fidelity.com </font>

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

<font style="FONT-FAMILY: Times New Roman" size="3">Past performance (before and after taxes) is not an indication of future performance.</font>

Bar Chart [Heading]

rr_BarChartHeading

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	17.20%	March 31, 2019
Lowest Quarter Return	-19.70%	December 31, 2018
Year-to-Date Return	-32.77%	March 31, 2020

Performance Table Heading

rr_PerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

<font style="FONT-FAMILY: Times New Roman" size="3">After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes.</font>

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

<font style="FONT-FAMILY: Times New Roman" size="3">The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan).</font>

Performance Table Explanation after Tax Higher

rr_PerformanceTableExplanationAfterTaxHigher

<font style="FONT-FAMILY: Times New Roman" size="3">Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.</font>

Performance Table Narrative

rr_PerformanceTableNarrativeTextBlock

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

02.28 Select Portfolios: Group 6 Industrials Sector Combo PRO-10 | Defense and Aerospace Portfolio | Defense and Aerospace Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Management fee

rr_ManagementFeesOverAssets

0.54%

Distribution and/or Service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

none

Other expenses

rr_OtherExpensesOverAssets

0.21%

Total annual operating expenses

rr_ExpensesOverAssets

0.75%

1 year

rr_ExpenseExampleYear01

$ 77

3 years

rr_ExpenseExampleYear03

240

5 years

rr_ExpenseExampleYear05

417

10 years

rr_ExpenseExampleYear10

$ 930

2010

rr_AnnualReturn2010

21.88%

2011

rr_AnnualReturn2011

7.33%

2012

rr_AnnualReturn2012

13.51%

2013

rr_AnnualReturn2013

48.14%

2014

rr_AnnualReturn2014

2.92%

2015

rr_AnnualReturn2015

3.60%

2016

rr_AnnualReturn2016

17.89%

2017

rr_AnnualReturn2017

34.21%

2018

rr_AnnualReturn2018

(6.74%)

2019

rr_AnnualReturn2019

33.74%

Year to Date Return, Label

rr_YearToDateReturnLabel

Year-to-Date Return

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Mar. 31, 2020

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

(32.77%)

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Highest Quarter Return

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Mar. 31, 2019

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

17.20%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Lowest Quarter Return

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Dec. 31, 2018

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(19.70%)

02.28 Select Portfolios: Group 6 Industrials Sector Combo PRO-10 | Defense and Aerospace Portfolio | Return Before Taxes | Defense and Aerospace Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Defense and Aerospace Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return Before Taxes</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

33.74%

Past 5 years

rr_AverageAnnualReturnYear05

15.37%

Past 10 years

rr_AverageAnnualReturnYear10

16.56%

02.28 Select Portfolios: Group 6 Industrials Sector Combo PRO-10 | Defense and Aerospace Portfolio | After Taxes on Distributions | Defense and Aerospace Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Defense and Aerospace Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

32.93%

Past 5 years

rr_AverageAnnualReturnYear05

13.88%

Past 10 years

rr_AverageAnnualReturnYear10

15.41%

02.28 Select Portfolios: Group 6 Industrials Sector Combo PRO-10 | Defense and Aerospace Portfolio | After Taxes on Distributions and Sales | Defense and Aerospace Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Defense and Aerospace Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions and Sale of Fund Shares</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

20.56%

Past 5 years

rr_AverageAnnualReturnYear05

12.04%

Past 10 years

rr_AverageAnnualReturnYear10

13.77%

02.28 Select Portfolios: Group 6 Industrials Sector Combo PRO-10 | Defense and Aerospace Portfolio | S&P 500® Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

31.49%

Past 5 years

rr_AverageAnnualReturnYear05

11.70%

Past 10 years

rr_AverageAnnualReturnYear10

13.56%

02.28 Select Portfolios: Group 6 Industrials Sector Combo PRO-10 | Defense and Aerospace Portfolio | MSCI U.S. IMI Aerospace & Defense 25-50 Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

34.05%

Past 5 years

rr_AverageAnnualReturnYear05

17.53%

Past 10 years

rr_AverageAnnualReturnYear10

18.79%

XML

Total

02.28 Select Portfolios: Group 6 Industrials Sector Combo PRO-10 | Industrials Portfolio

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: bold 12pt Arial, Helvetica, sans-serif;">Fund:<br/>Industrials Portfolio</p>

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

The fund seeks capital appreciation.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

Shareholder Fees {- Industrials Portfolio}	02.28 Select Portfolios: Group 6 Industrials Sector Combo PRO-10 Industrials Portfolio USD ($)
(fees paid directly from your investment)	none

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Annual Operating Expenses {- Industrials Portfolio}	02.28 Select Portfolios: Group 6 Industrials Sector Combo PRO-10 Industrials Portfolio Industrials Portfolio-Default
Management fee	0.54%
Distribution and/or Service (12b-1) fees	none
Other expenses	0.22%
Total annual operating expenses	0.76%

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Expense Example {- Industrials Portfolio}	02.28 Select Portfolios: Group 6 Industrials Sector Combo PRO-10 Industrials Portfolio Industrials Portfolio-Default USD ($)
1 year	$ 78
3 years	243
5 years	422
10 years	$ 942

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 143% of the average value of its portfolio.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in the research, development, manufacture, distribution, supply, or sale of industrial products, services, or equipment.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Industrials Industry Concentration. Industrial industries can be significantly affected by general economic trends, changes in consumer sentiment and spending, commodity prices, legislation, government regulation and spending, import controls, worldwide competition, and liability for environmental damage, depletion of resources, and mandated expenditures for safety and pollution control.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

• High Portfolio Turnover. High portfolio turnover (more than 100%) may result in increased transaction costs and potentially higher capital gains or losses. The effects of higher than normal portfolio turnover may adversely affect the fund's performance.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	17.89%	March 31, 2019
Lowest Quarter Return	-22.42%	September 30, 2011
Year-to-Date Return	-28.64%	March 31, 2020

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

Average Annual Total Returns{- Industrials Portfolio} - 02.28 Select Portfolios: Group 6 Industrials Sector Combo PRO-10 - Industrials Portfolio	Past 1 year	Past 5 years	Past 10 years
Industrials Portfolio-Default | Return Before Taxes	27.99%	8.08%	12.53%
Industrials Portfolio-Default | After Taxes on Distributions	26.77%	6.64%	11.20%
Industrials Portfolio-Default | After Taxes on Distributions and Sales	17.44%	6.16%	10.19%
S&P 500® Index(reflects no deduction for fees, expenses, or taxes)	31.49%	11.70%	13.56%
MSCI U.S. IMI Industrials 25-50 Index(reflects no deduction for fees, expenses, or taxes)	30.28%	9.65%	13.61%

XML

Label

Element

Value

Risk/Return:

rr_RiskReturnAbstract

Registrant Name

dei_EntityRegistrantName

FIDELITY SELECT PORTFOLIOS

Prospectus Date

rr_ProspectusDate

Apr. 29, 2020

02.28 Select Portfolios: Group 6 Industrials Sector Combo PRO-10 | Air Transportation Portfolio

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: bold 12pt Arial, Helvetica, sans-serif;">Fund:<br/>Air Transportation Portfolio</p>

Objective [Heading]

rr_ObjectiveHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks capital appreciation.

Expense [Heading]

rr_ExpenseHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

Shareholder Fees Caption [Text]

rr_ShareholderFeesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

(fees paid directly from your investment)

rr_ShareholderFeeOther

none

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

Portfolio Turnover [Text Block]

rr_PortfolioTurnoverTextBlock

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 95% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

95.00%

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Strategy [Heading]

rr_StrategyHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in the regional, national, and international movement of passengers, mail, and freight via aircraft.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

Strategy Portfolio Concentration [Text]

rr_StrategyPortfolioConcentration

<font style="FONT-FAMILY: Times New Roman" size="3">Normally investing at least 80% of assets in securities of companies principally engaged in the regional, national, and international movement of passengers, mail, and freight via aircraft.</font>

Risk [Heading]

rr_RiskHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Air Transportation Industry Concentration. The air transportation industry can be significantly affected by competition within the industry, domestic and foreign economies, government regulation, labor relations, the price of fuel, and geopolitical developments.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

Risk Lose Money [Text]

rr_RiskLoseMoney

<font style="FONT-FAMILY: Times New Roman" size="3">You could lose money by investing in the fund.</font>

Risk Nondiversified Status [Text]

rr_RiskNondiversifiedStatus

<font style="FONT-FAMILY: Times New Roman" size="3">In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.</font>

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

<font style="FONT-FAMILY: Times New Roman" size="3">An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</font>

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

<font style="FONT-FAMILY: Times New Roman" size="3">The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time.</font>

Performance Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

<font style="FONT-FAMILY: Times New Roman" size="3">www.fidelity.com </font>

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

<font style="FONT-FAMILY: Times New Roman" size="3">Past performance (before and after taxes) is not an indication of future performance.</font>

Bar Chart [Heading]

rr_BarChartHeading

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	21.51%	March 31, 2010
Lowest Quarter Return	-17.00%	December 31, 2018
Year-to-Date Return	-42.40%	March 31, 2020

Performance Table Heading

rr_PerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

<font style="FONT-FAMILY: Times New Roman" size="3">After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes.</font>

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

<font style="FONT-FAMILY: Times New Roman" size="3">The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan).</font>

Performance Table Explanation after Tax Higher

rr_PerformanceTableExplanationAfterTaxHigher

<font style="FONT-FAMILY: Times New Roman" size="3">Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.</font>

Performance Table Narrative

rr_PerformanceTableNarrativeTextBlock

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

02.28 Select Portfolios: Group 6 Industrials Sector Combo PRO-10 | Air Transportation Portfolio | Air Transportation Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Management fee

rr_ManagementFeesOverAssets

0.54%

Distribution and/or Service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

none

Other expenses

rr_OtherExpensesOverAssets

0.27%

Total annual operating expenses

rr_ExpensesOverAssets

0.81%

1 year

rr_ExpenseExampleYear01

$ 83

3 years

rr_ExpenseExampleYear03

259

5 years

rr_ExpenseExampleYear05

450

10 years

rr_ExpenseExampleYear10

$ 1,002

2010

rr_AnnualReturn2010

33.37%

2011

rr_AnnualReturn2011

(6.07%)

2012

rr_AnnualReturn2012

19.16%

2013

rr_AnnualReturn2013

50.65%

2014

rr_AnnualReturn2014

28.08%

2015

rr_AnnualReturn2015

(8.61%)

2016

rr_AnnualReturn2016

20.03%

2017

rr_AnnualReturn2017

24.32%

2018

rr_AnnualReturn2018

(12.46%)

2019

rr_AnnualReturn2019

21.00%

Year to Date Return, Label

rr_YearToDateReturnLabel

Year-to-Date Return

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Mar. 31, 2020

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

(42.40%)

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Highest Quarter Return

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Mar. 31, 2010

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

21.51%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Lowest Quarter Return

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Dec. 31, 2018

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(17.00%)

02.28 Select Portfolios: Group 6 Industrials Sector Combo PRO-10 | Air Transportation Portfolio | Return Before Taxes | Air Transportation Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Air Transportation Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return Before Taxes</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

21.00%

Past 5 years

rr_AverageAnnualReturnYear05

7.63%

Past 10 years

rr_AverageAnnualReturnYear10

15.32%

02.28 Select Portfolios: Group 6 Industrials Sector Combo PRO-10 | Air Transportation Portfolio | After Taxes on Distributions | Air Transportation Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Air Transportation Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

18.51%

Past 5 years

rr_AverageAnnualReturnYear05

5.61%

Past 10 years

rr_AverageAnnualReturnYear10

13.84%

02.28 Select Portfolios: Group 6 Industrials Sector Combo PRO-10 | Air Transportation Portfolio | After Taxes on Distributions and Sales | Air Transportation Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Air Transportation Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions and Sale of Fund Shares</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

14.07%

Past 5 years

rr_AverageAnnualReturnYear05

5.68%

Past 10 years

rr_AverageAnnualReturnYear10

12.69%

02.28 Select Portfolios: Group 6 Industrials Sector Combo PRO-10 | Air Transportation Portfolio | S&P 500® Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

31.49%

Past 5 years

rr_AverageAnnualReturnYear05

11.70%

Past 10 years

rr_AverageAnnualReturnYear10

13.56%

02.28 Select Portfolios: Group 6 Industrials Sector Combo PRO-10 | Air Transportation Portfolio | Nasdaq North America Air Transportation Linked Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

24.19%

Past 5 years

rr_AverageAnnualReturnYear05

9.58%

Past 10 years

rr_AverageAnnualReturnYear10

15.51%

XML

Total

02.28 Select Portfolios: Group 5 Health Care Sector Combo PRO-13 | Health Care Portfolio

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: bold 12pt Arial, Helvetica, sans-serif;">Fund:<br/>Health Care Portfolio</p>

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

The fund seeks capital appreciation.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

Shareholder Fees {- Health Care Portfolio}	02.28 Select Portfolios: Group 5 Health Care Sector Combo PRO-13 Health Care Portfolio USD ($)
(fees paid directly from your investment)	none

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Annual Operating Expenses {- Health Care Portfolio}	02.28 Select Portfolios: Group 5 Health Care Sector Combo PRO-13 Health Care Portfolio Health Care Portfolio-Default
Management fee	0.54%
Distribution and/or Service (12b-1) fees	none
Other expenses	0.16%
Total annual operating expenses	0.70%

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Expense Example {- Health Care Portfolio}	02.28 Select Portfolios: Group 5 Health Care Sector Combo PRO-13 Health Care Portfolio Health Care Portfolio-Default USD ($)
1 year	$ 72
3 years	224
5 years	390
10 years	$ 871

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 36% of the average value of its portfolio.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in the design, manufacture, or sale of products or services used for or in connection with health care or medicine.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Health Care Industry Concentration. The health care industries are subject to government regulation and reimbursement rates, as well as government approval of products and services, which could have a significant effect on price and availability, and can be significantly affected by product liability claims, rapid obsolescence, and patent expirations.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	22.15%	December 31, 2019
Lowest Quarter Return	-15.01%	December 31, 2018
Year-to-Date Return	-11.05%	March 31, 2020

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

Average Annual Total Returns{- Health Care Portfolio} - 02.28 Select Portfolios: Group 5 Health Care Sector Combo PRO-13 - Health Care Portfolio	Past 1 year	Past 5 years	Past 10 years
Health Care Portfolio-Default | Return Before Taxes	31.46%	10.77%	18.15%
Health Care Portfolio-Default | After Taxes on Distributions	31.04%	9.42%	16.30%
Health Care Portfolio-Default | After Taxes on Distributions and Sales	18.92%	8.17%	14.80%
S&P 500® Index(reflects no deduction for fees, expenses, or taxes)	31.49%	11.70%	13.56%
MSCI U.S. IMI Health Care 25-50 Index(reflects no deduction for fees, expenses, or taxes)	22.03%	10.54%	15.26%

XML

Label

Element

Value

Risk/Return:

rr_RiskReturnAbstract

Registrant Name

dei_EntityRegistrantName

FIDELITY SELECT PORTFOLIOS

Prospectus Date

rr_ProspectusDate

Apr. 29, 2020

02.28 Select Portfolios: Group 7 Information Technology Sector Combo PRO-16 | Technology Portfolio

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: bold 12pt Arial, Helvetica, sans-serif;">Fund:<br/>Technology Portfolio</p>

Objective [Heading]

rr_ObjectiveHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks capital appreciation.

Expense [Heading]

rr_ExpenseHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

Shareholder Fees Caption [Text]

rr_ShareholderFeesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

(fees paid directly from your investment)

rr_ShareholderFeeOther

none

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

Portfolio Turnover [Text Block]

rr_PortfolioTurnoverTextBlock

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 32% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

32.00%

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Strategy [Heading]

rr_StrategyHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in offering, using, or developing products, processes, or services that will provide or will benefit significantly from technological advances and improvements.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

Strategy Portfolio Concentration [Text]

rr_StrategyPortfolioConcentration

<font style="FONT-FAMILY: Times New Roman" size="3">Normally investing at least 80% of assets in securities of companies principally engaged in offering, using, or developing products, processes, or services that will provide or will benefit significantly from technological advances and improvements.</font>

Risk [Heading]

rr_RiskHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets, particularly emerging markets, can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Technology Industry Concentration. The technology industries can be significantly affected by obsolescence of existing technology, short product cycles, falling prices and profits, competition from new market entrants, and general economic conditions.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

Risk Lose Money [Text]

rr_RiskLoseMoney

<font style="FONT-FAMILY: Times New Roman" size="3">You could lose money by investing in the fund.</font>

Risk Nondiversified Status [Text]

rr_RiskNondiversifiedStatus

<font style="FONT-FAMILY: Times New Roman" size="3">In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.</font>

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

<font style="FONT-FAMILY: Times New Roman" size="3">An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</font>

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

<font style="FONT-FAMILY: Times New Roman" size="3">The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time.</font>

Performance Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

<font style="FONT-FAMILY: Times New Roman" size="3">www.fidelity.com </font>

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

<font style="FONT-FAMILY: Times New Roman" size="3">Past performance (before and after taxes) is not an indication of future performance.</font>

Bar Chart [Heading]

rr_BarChartHeading

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	22.17%	March 31, 2012
Lowest Quarter Return	-22.49%	December 31, 2018
Year-to-Date Return	-11.46%	March 31, 2020

Performance Table Heading

rr_PerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

<font style="FONT-FAMILY: Times New Roman" size="3">After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes.</font>

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

<font style="FONT-FAMILY: Times New Roman" size="3">The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan).</font>

Performance Table Explanation after Tax Higher

rr_PerformanceTableExplanationAfterTaxHigher

<font style="FONT-FAMILY: Times New Roman" size="3">Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.</font>

Performance Table Narrative

rr_PerformanceTableNarrativeTextBlock

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

02.28 Select Portfolios: Group 7 Information Technology Sector Combo PRO-16 | Technology Portfolio | Technology Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Management fee

rr_ManagementFeesOverAssets

0.54%

Distribution and/or Service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

none

Other expenses

rr_OtherExpensesOverAssets

0.17%

Total annual operating expenses

rr_ExpensesOverAssets

0.71%

1 year

rr_ExpenseExampleYear01

$ 73

3 years

rr_ExpenseExampleYear03

227

5 years

rr_ExpenseExampleYear05

395

10 years

rr_ExpenseExampleYear10

$ 883

2010

rr_AnnualReturn2010

26.69%

2011

rr_AnnualReturn2011

(9.56%)

2012

rr_AnnualReturn2012

17.16%

2013

rr_AnnualReturn2013

31.76%

2014

rr_AnnualReturn2014

10.65%

2015

rr_AnnualReturn2015

7.40%

2016

rr_AnnualReturn2016

11.94%

2017

rr_AnnualReturn2017

49.86%

2018

rr_AnnualReturn2018

(8.79%)

2019

rr_AnnualReturn2019

51.07%

Year to Date Return, Label

rr_YearToDateReturnLabel

Year-to-Date Return

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Mar. 31, 2020

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

(11.46%)

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Highest Quarter Return

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Mar. 31, 2012

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

22.17%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Lowest Quarter Return

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Dec. 31, 2018

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(22.49%)

02.28 Select Portfolios: Group 7 Information Technology Sector Combo PRO-16 | Technology Portfolio | Return Before Taxes | Technology Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Technology Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return Before Taxes</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

51.07%

Past 5 years

rr_AverageAnnualReturnYear05

19.94%

Past 10 years

rr_AverageAnnualReturnYear10

17.13%

02.28 Select Portfolios: Group 7 Information Technology Sector Combo PRO-16 | Technology Portfolio | After Taxes on Distributions | Technology Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Technology Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

50.40%

Past 5 years

rr_AverageAnnualReturnYear05

17.64%

Past 10 years

rr_AverageAnnualReturnYear10

15.09%

02.28 Select Portfolios: Group 7 Information Technology Sector Combo PRO-16 | Technology Portfolio | After Taxes on Distributions and Sales | Technology Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Technology Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions and Sale of Fund Shares</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

30.70%

Past 5 years

rr_AverageAnnualReturnYear05

15.45%

Past 10 years

rr_AverageAnnualReturnYear10

13.63%

02.28 Select Portfolios: Group 7 Information Technology Sector Combo PRO-16 | Technology Portfolio | S&P 500® Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

31.49%

Past 5 years

rr_AverageAnnualReturnYear05

11.70%

Past 10 years

rr_AverageAnnualReturnYear10

13.56%

02.28 Select Portfolios: Group 7 Information Technology Sector Combo PRO-16 | Technology Portfolio | MSCI U.S. IMI Information Technology 25-50 Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

48.85%

Past 5 years

rr_AverageAnnualReturnYear05

19.53%

Past 10 years

rr_AverageAnnualReturnYear10

17.26%

XML

Label

Element

Value

Risk/Return:

rr_RiskReturnAbstract

Registrant Name

dei_EntityRegistrantName

FIDELITY SELECT PORTFOLIOS

Prospectus Date

rr_ProspectusDate

Apr. 29, 2020

02.28 Select Portfolios: Group 7 Information Technology Sector Combo PRO-16 | IT Services Portfolio

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: bold 12pt Arial, Helvetica, sans-serif;">Fund:<br/>IT Services Portfolio</p>

Objective [Heading]

rr_ObjectiveHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks capital appreciation.

Expense [Heading]

rr_ExpenseHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

Shareholder Fees Caption [Text]

rr_ShareholderFeesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

(fees paid directly from your investment)

rr_ShareholderFeeOther

none

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

Portfolio Turnover [Text Block]

rr_PortfolioTurnoverTextBlock

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 24% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

24.00%

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Strategy [Heading]

rr_StrategyHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in providing information technology services.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

Strategy Portfolio Concentration [Text]

rr_StrategyPortfolioConcentration

<font style="FONT-FAMILY: Times New Roman" size="3">Normally investing at least 80% of assets in securities of companies principally engaged in providing information technology services.</font>

Risk [Heading]

rr_RiskHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• IT Services Industry Concentration. The IT services industry can be significantly affected by competitive pressures, such as technological developments, fixed-rate pricing, and the ability to attract and retain skilled employees, and the success of companies in the industry is subject to continued demand for IT services.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

Risk Lose Money [Text]

rr_RiskLoseMoney

<font style="FONT-FAMILY: Times New Roman" size="3">You could lose money by investing in the fund.</font>

Risk Nondiversified Status [Text]

rr_RiskNondiversifiedStatus

<font style="FONT-FAMILY: Times New Roman" size="3">In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.</font>

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

<font style="FONT-FAMILY: Times New Roman" size="3">An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</font>

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

<font style="FONT-FAMILY: Times New Roman" size="3">The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time.</font>

Performance Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

<font style="FONT-FAMILY: Times New Roman" size="3">www.fidelity.com </font>

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

<font style="FONT-FAMILY: Times New Roman" size="3">Past performance (before and after taxes) is not an indication of future performance.</font>

Bar Chart [Heading]

rr_BarChartHeading

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	25.49%	March 31, 2019
Lowest Quarter Return	-17.05%	December 31, 2018
Year-to-Date Return	-16.20%	March 31, 2020

Performance Table Heading

rr_PerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

<font style="FONT-FAMILY: Times New Roman" size="3">After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes.</font>

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

<font style="FONT-FAMILY: Times New Roman" size="3">The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan).</font>

Performance Table Explanation after Tax Higher

rr_PerformanceTableExplanationAfterTaxHigher

<font style="FONT-FAMILY: Times New Roman" size="3">Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.</font>

Performance Table Narrative

rr_PerformanceTableNarrativeTextBlock

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

02.28 Select Portfolios: Group 7 Information Technology Sector Combo PRO-16 | IT Services Portfolio | IT Services Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Management fee

rr_ManagementFeesOverAssets

0.54%

Distribution and/or Service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

none

Other expenses

rr_OtherExpensesOverAssets

0.19%

Total annual operating expenses

rr_ExpensesOverAssets

0.73%

1 year

rr_ExpenseExampleYear01

$ 75

3 years

rr_ExpenseExampleYear03

233

5 years

rr_ExpenseExampleYear05

406

10 years

rr_ExpenseExampleYear10

$ 906

2010

rr_AnnualReturn2010

18.45%

2011

rr_AnnualReturn2011

2.25%

2012

rr_AnnualReturn2012

19.82%

2013

rr_AnnualReturn2013

53.12%

2014

rr_AnnualReturn2014

6.28%

2015

rr_AnnualReturn2015

13.13%

2016

rr_AnnualReturn2016

5.19%

2017

rr_AnnualReturn2017

34.25%

2018

rr_AnnualReturn2018

4.19%

2019

rr_AnnualReturn2019

42.23%

Year to Date Return, Label

rr_YearToDateReturnLabel

Year-to-Date Return

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Mar. 31, 2020

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

(16.20%)

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Highest Quarter Return

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Mar. 31, 2019

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

25.49%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Lowest Quarter Return

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Dec. 31, 2018

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(17.05%)

02.28 Select Portfolios: Group 7 Information Technology Sector Combo PRO-16 | IT Services Portfolio | Return Before Taxes | IT Services Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

IT Services Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return Before Taxes</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

42.23%

Past 5 years

rr_AverageAnnualReturnYear05

18.81%

Past 10 years

rr_AverageAnnualReturnYear10

18.78%

02.28 Select Portfolios: Group 7 Information Technology Sector Combo PRO-16 | IT Services Portfolio | After Taxes on Distributions | IT Services Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

IT Services Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

41.45%

Past 5 years

rr_AverageAnnualReturnYear05

17.98%

Past 10 years

rr_AverageAnnualReturnYear10

17.98%

02.28 Select Portfolios: Group 7 Information Technology Sector Combo PRO-16 | IT Services Portfolio | After Taxes on Distributions and Sales | IT Services Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

IT Services Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions and Sale of Fund Shares</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

25.54%

Past 5 years

rr_AverageAnnualReturnYear05

15.10%

Past 10 years

rr_AverageAnnualReturnYear10

15.87%

02.28 Select Portfolios: Group 7 Information Technology Sector Combo PRO-16 | IT Services Portfolio | S&P 500® Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

31.49%

Past 5 years

rr_AverageAnnualReturnYear05

11.70%

Past 10 years

rr_AverageAnnualReturnYear10

13.56%

02.28 Select Portfolios: Group 7 Information Technology Sector Combo PRO-16 | IT Services Portfolio | MSCI U.S. IMI Information Technology Services 25-50 Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

41.01%

Past 5 years

rr_AverageAnnualReturnYear05

17.66%

Past 10 years

rr_AverageAnnualReturnYear10

17.13%

XML

Label

Element

Value

Risk/Return:

rr_RiskReturnAbstract

Registrant Name

dei_EntityRegistrantName

FIDELITY SELECT PORTFOLIOS

Prospectus Date

rr_ProspectusDate

Apr. 29, 2020

02.28 Select Portfolios: Group 7 Information Technology Sector Combo PRO-16 | Semiconductors Portfolio

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: bold 12pt Arial, Helvetica, sans-serif;">Fund:<br/>Semiconductors Portfolio</p>

Objective [Heading]

rr_ObjectiveHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks capital appreciation.

Expense [Heading]

rr_ExpenseHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

Shareholder Fees Caption [Text]

rr_ShareholderFeesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

(fees paid directly from your investment)

rr_ShareholderFeeOther

none

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

Portfolio Turnover [Text Block]

rr_PortfolioTurnoverTextBlock

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 114% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

114.00%

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Strategy [Heading]

rr_StrategyHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in the design, manufacture, or sale of semiconductors and semiconductor equipment.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

Strategy Portfolio Concentration [Text]

rr_StrategyPortfolioConcentration

<font style="FONT-FAMILY: Times New Roman" size="3">Normally investing at least 80% of assets in securities of companies principally engaged in the design, manufacture, or sale of semiconductors and semiconductor equipment.</font>

Risk [Heading]

rr_RiskHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Electronics Industry Concentration. The electronics industry can be significantly affected by rapid obsolescence, intense competition, and global demand.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

• High Portfolio Turnover. High portfolio turnover (more than 100%) may result in increased transaction costs and potentially higher capital gains or losses. The effects of higher than normal portfolio turnover may adversely affect the fund's performance.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

Risk Lose Money [Text]

rr_RiskLoseMoney

<font style="FONT-FAMILY: Times New Roman" size="3">You could lose money by investing in the fund.</font>

Risk Nondiversified Status [Text]

rr_RiskNondiversifiedStatus

<font style="FONT-FAMILY: Times New Roman" size="3">In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.</font>

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

<font style="FONT-FAMILY: Times New Roman" size="3">An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</font>

Bar Chart and Performance Table [Heading]

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<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

Performance Narrative [Text Block]

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The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

<font style="FONT-FAMILY: Times New Roman" size="3">The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time.</font>

Performance Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

<font style="FONT-FAMILY: Times New Roman" size="3">www.fidelity.com </font>

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

<font style="FONT-FAMILY: Times New Roman" size="3">Past performance (before and after taxes) is not an indication of future performance.</font>

Bar Chart [Heading]

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<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	23.64%	March 31, 2012
Lowest Quarter Return	-16.86%	September 30, 2011
Year-to-Date Return	-20.13%	March 31, 2020

Performance Table Heading

rr_PerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

<font style="FONT-FAMILY: Times New Roman" size="3">After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes.</font>

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

<font style="FONT-FAMILY: Times New Roman" size="3">The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan).</font>

Performance Table Explanation after Tax Higher

rr_PerformanceTableExplanationAfterTaxHigher

<font style="FONT-FAMILY: Times New Roman" size="3">Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.</font>

Performance Table Narrative

rr_PerformanceTableNarrativeTextBlock

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

02.28 Select Portfolios: Group 7 Information Technology Sector Combo PRO-16 | Semiconductors Portfolio | Semiconductors Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Management fee

rr_ManagementFeesOverAssets

0.54%

Distribution and/or Service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

none

Other expenses

rr_OtherExpensesOverAssets

0.18%

Total annual operating expenses

rr_ExpensesOverAssets

0.72%

1 year

rr_ExpenseExampleYear01

$ 74

3 years

rr_ExpenseExampleYear03

230

5 years

rr_ExpenseExampleYear05

401

10 years

rr_ExpenseExampleYear10

$ 894

2010

rr_AnnualReturn2010

16.84%

2011

rr_AnnualReturn2011

(8.49%)

2012

rr_AnnualReturn2012

3.60%

2013

rr_AnnualReturn2013

39.18%

2014

rr_AnnualReturn2014

38.37%

2015

rr_AnnualReturn2015

2.24%

2016

rr_AnnualReturn2016

32.38%

2017

rr_AnnualReturn2017

35.06%

2018

rr_AnnualReturn2018

(11.75%)

2019

rr_AnnualReturn2019

64.46%

Year to Date Return, Label

rr_YearToDateReturnLabel

Year-to-Date Return

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Mar. 31, 2020

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

(20.13%)

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Highest Quarter Return

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Mar. 31, 2012

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

23.64%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Lowest Quarter Return

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Sep. 30, 2011

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(16.86%)

02.28 Select Portfolios: Group 7 Information Technology Sector Combo PRO-16 | Semiconductors Portfolio | Return Before Taxes | Semiconductors Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Semiconductors Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return Before Taxes</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

64.46%

Past 5 years

rr_AverageAnnualReturnYear05

21.55%

Past 10 years

rr_AverageAnnualReturnYear10

18.92%

02.28 Select Portfolios: Group 7 Information Technology Sector Combo PRO-16 | Semiconductors Portfolio | After Taxes on Distributions | Semiconductors Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Semiconductors Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

63.18%

Past 5 years

rr_AverageAnnualReturnYear05

17.45%

Past 10 years

rr_AverageAnnualReturnYear10

16.75%

02.28 Select Portfolios: Group 7 Information Technology Sector Combo PRO-16 | Semiconductors Portfolio | After Taxes on Distributions and Sales | Semiconductors Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Semiconductors Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions and Sale of Fund Shares</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

39.07%

Past 5 years

rr_AverageAnnualReturnYear05

15.72%

Past 10 years

rr_AverageAnnualReturnYear10

15.20%

02.28 Select Portfolios: Group 7 Information Technology Sector Combo PRO-16 | Semiconductors Portfolio | S&P 500® Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

31.49%

Past 5 years

rr_AverageAnnualReturnYear05

11.70%

Past 10 years

rr_AverageAnnualReturnYear10

13.56%

02.28 Select Portfolios: Group 7 Information Technology Sector Combo PRO-16 | Semiconductors Portfolio | MSCI U.S. IMI Semiconductors & Semiconductor Equipment 25-50 Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

55.25%

Past 5 years

rr_AverageAnnualReturnYear05

20.18%

Past 10 years

rr_AverageAnnualReturnYear10

17.45%

XML

Label

Element

Value

Risk/Return:

rr_RiskReturnAbstract

Registrant Name

dei_EntityRegistrantName

FIDELITY SELECT PORTFOLIOS

Prospectus Date

rr_ProspectusDate

Apr. 29, 2020

02.28 Select Portfolios: Fidelity Advisor Gold Fund - AMCIZ PRO-12 | Gold Portfolio

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: normal 12pt Arial, Helvetica, sans-serif;"><b>Fund/Class</b>:<br/><b>Gold Portfolio</b>/Fidelity Advisor® Gold Fund A, M, C, I, Z</p>

Objective [Heading]

rr_ObjectiveHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks capital appreciation.

Expense [Heading]

rr_ExpenseHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund. In addition to the fees and expenses described below, your broker may also require you to pay brokerage commissions on purchases and sales of certain share classes of the fund.

You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $50,000 in the fund or certain other Fidelity^® funds. More information about these and other discounts is available from your investment professional and in the "Fund Distribution" section beginning on page 29 of the prospectus. Different intermediaries may provide additional waivers or reductions of the sales charge. Please see “Sales Charge Waiver Policies Applied by Certain Intermediaries” in the “Appendix” section of the prospectus.

Shareholder Fees Caption [Text]

rr_ShareholderFeesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(fees paid directly from your investment)</p>

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

Portfolio Turnover [Text Block]

rr_PortfolioTurnoverTextBlock

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 56% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

56.00%

Expense Breakpoint Discounts [Text]

rr_ExpenseBreakpointDiscounts

<font style="FONT-FAMILY: Times New Roman" size="3">You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $50,000 in the fund or certain other Fidelity® funds. More information about these and other discounts is available from your investment professional and in the "Fund Distribution" section beginning on page 29 of the prospectus.</font>

Expense Breakpoint, Minimum Investment Required [Amount]

rr_ExpenseBreakpointMinimumInvestmentRequiredAmount

$ 50,000

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated and if you hold your shares:

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Expense Example, No Redemption, By Year, Caption [Text]

rr_ExpenseExampleNoRedemptionByYearCaption

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Hold Shares</p>

Strategy [Heading]

rr_StrategyHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

• Normally investing primarily in common stocks and in certain precious metals.

• Investing primarily in companies engaged in exploration, mining, processing, or dealing in gold, or to a lesser degree, in silver, platinum, diamonds, or other precious metals and minerals.

• Normally investing at least 80% of assets in securities of companies principally engaged in gold-related activities, and in gold bullion or coins.

• Investing up to 25% of assets in gold and other precious metals through a wholly-owned subsidiary organized under the laws of the Cayman Islands.

• Potentially investing in other precious metals, instruments whose value is linked to the price of precious metals, and securities of companies that manufacture and distribute precious metal and minerals products (such as jewelry, watches, and metal foil and leaf) and companies that invest in other companies engaged in gold and other precious metal and mineral-related activities.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

Strategy Portfolio Concentration [Text]

rr_StrategyPortfolioConcentration

<font style="FONT-FAMILY: Times New Roman" size="3">Normally investing at least 80% of assets in securities of companies principally engaged in gold-related activities, and in gold bullion or coins.</font>

Risk [Heading]

rr_RiskHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets, particularly emerging markets, can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market. Emerging markets can be subject to greater social, economic, regulatory, and political uncertainties and can be extremely volatile. Foreign exchange rates also can be extremely volatile.

• Geographic Concentration in Canada. Because an underlying fund concentrates its investments in Canada, the underlying fund's performance is expected to be closely tied to social, political, and economic conditions within Canada and to be more volatile than the performance of more geographically diversified funds. In addition, because the underlying fund may invest a significant percentage of assets in certain industries, the underlying fund's performance could be affected to the extent that the particular industry or industries in which the fund invests are sensitive to adverse social, political, economic, currency, or regulatory developments.

• Gold Industry Concentration. The gold industry can be significantly affected by international monetary and political developments such as currency devaluations or revaluations, central bank movements, economic and social conditions within a country, trade imbalances, or trade or currency restrictions between countries, as well as supply and demand for gold and operational costs associated with mining.

• Subsidiary Risk. Investment in Fidelity Select Gold Cayman Ltd., an unregistered subsidiary, is not subject to the investor protections of the Investment Company Act of 1940 (1940 Act) and is subject to the risks associated with the gold industry. Changes in tax and other laws could negatively affect investments in the subsidiary.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the 1940 Act, which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

Risk Lose Money [Text]

rr_RiskLoseMoney

<font style="FONT-FAMILY: Times New Roman" size="3">You could lose money by investing in the fund.</font>

Risk Nondiversified Status [Text]

rr_RiskNondiversifiedStatus

<font style="FONT-FAMILY: Times New Roman" size="3">In addition, the fund is classified as non-diversified under the 1940 Act, which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.</font>

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

<font style="FONT-FAMILY: Times New Roman" size="3">An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</font>

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit institutional.fidelity.com for more recent performance information.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

<font style="FONT-FAMILY: Times New Roman" size="3">The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time.</font>

Performance Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

<font style="FONT-FAMILY: Times New Roman" size="3">institutional.fidelity.com</font>

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

<font style="FONT-FAMILY: Times New Roman" size="3">Past performance (before and after taxes) is not an indication of future performance.</font>

Bar Chart [Heading]

rr_BarChartHeading

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

Bar Chart Narrative [Text Block]

rr_BarChartNarrativeTextBlock

The returns in the bar chart do not reflect any applicable sales charges; if sales charges were reflected, returns would be lower than those shown.

Bar Chart Does Not Reflect Sales Loads [Text]

rr_BarChartDoesNotReflectSalesLoads

<font style="FONT-FAMILY: Times New Roman" size="3">The returns in the bar chart do not reflect any applicable sales charges; if sales charges were reflected, returns would be lower than those shown.</font>

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

During the periods shown in the chart for Class A:	Returns	Quarter ended
Highest Quarter Return	40.94%	March 31, 2016
Lowest Quarter Return	-37.42%	June 30, 2013
Year-to-Date Return	-19.14%	March 31, 2020

Performance Table Heading

rr_PerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

Performance Table Does Reflect Sales Loads

rr_PerformanceTableDoesReflectSalesLoads

<font style="FONT-FAMILY: Times New Roman" size="3">Unlike the returns in the bar chart, the returns in the table reflect the maximum applicable sales charges.</font>

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

<font style="FONT-FAMILY: Times New Roman" size="3">After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes.</font>

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

<font style="FONT-FAMILY: Times New Roman" size="3">The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan).</font>

Performance Table One Class of after Tax Shown [Text]

rr_PerformanceTableOneClassOfAfterTaxShown

<font style="FONT-FAMILY: Times New Roman" size="3">After-tax returns for Class A are shown in the table below and after-tax returns for other classes will vary.</font>

Performance Table Explanation after Tax Higher

rr_PerformanceTableExplanationAfterTaxHigher

<font style="FONT-FAMILY: Times New Roman" size="3">Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.</font>

Performance Table Narrative

rr_PerformanceTableNarrativeTextBlock

Unlike the returns in the bar chart, the returns in the table reflect the maximum applicable sales charges. After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. After-tax returns for Class A are shown in the table below and after-tax returns for other classes will vary. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

02.28 Select Portfolios: Fidelity Advisor Gold Fund - AMCIZ PRO-12 | Gold Portfolio | Fidelity Advisor Gold Fund: Class A

Risk/Return:

rr_RiskReturnAbstract

Maximum sales charge (load) on purchases (as a % of offering price)

rr_MaximumCumulativeSalesChargeOverOfferingPrice

5.75%

Maximum contingent deferred sales charge (as a % of the lesser of original purchase price or redemption proceeds)

rr_MaximumDeferredSalesChargeOverOther

none

^[1]

Management fee

rr_ManagementFeesOverAssets

0.54%

Distribution and/or Service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

0.25%

Other expenses

rr_OtherExpensesOverAssets

0.34%

Total annual operating expenses

rr_ExpensesOverAssets

1.13%

Expenses Deferred Charges [Text Block]

rr_ExpensesDeferredChargesTextBlock

Class A and Class M purchases of $1 million or more will not be subject to a front-end sales charge. Such Class A and Class M purchases may be subject, upon redemption, to a contingent deferred sales charge (CDSC) of 1.00% or 0.25%, respectively.

1 year

rr_ExpenseExampleYear01

$ 684

3 years

rr_ExpenseExampleYear03

913

5 years

rr_ExpenseExampleYear05

1,161

10 years

rr_ExpenseExampleYear10

1,871

1 Year

rr_ExpenseExampleNoRedemptionYear01

684

3 Years

rr_ExpenseExampleNoRedemptionYear03

913

5 Years

rr_ExpenseExampleNoRedemptionYear05

1,161

10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 1,871

2010

rr_AnnualReturn2010

34.92%

2011

rr_AnnualReturn2011

(16.56%)

2012

rr_AnnualReturn2012

(12.63%)

2013

rr_AnnualReturn2013

(51.54%)

2014

rr_AnnualReturn2014

(8.83%)

2015

rr_AnnualReturn2015

(18.07%)

2016

rr_AnnualReturn2016

46.80%

2017

rr_AnnualReturn2017

8.28%

2018

rr_AnnualReturn2018

(13.28%)

2019

rr_AnnualReturn2019

35.05%

Year to Date Return, Label

rr_YearToDateReturnLabel

Year-to-Date Return

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Mar. 31, 2020

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

(19.14%)

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Highest Quarter Return

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Mar. 31, 2016

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

40.94%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Lowest Quarter Return

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Jun. 30, 2013

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(37.42%)

02.28 Select Portfolios: Fidelity Advisor Gold Fund - AMCIZ PRO-12 | Gold Portfolio | Fidelity Advisor Gold Fund: Class M

Risk/Return:

rr_RiskReturnAbstract

Maximum sales charge (load) on purchases (as a % of offering price)

rr_MaximumCumulativeSalesChargeOverOfferingPrice

3.50%

Maximum contingent deferred sales charge (as a % of the lesser of original purchase price or redemption proceeds)

rr_MaximumDeferredSalesChargeOverOther

none

^[1]

Management fee

rr_ManagementFeesOverAssets

0.54%

Distribution and/or Service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

0.50%

Other expenses

rr_OtherExpensesOverAssets

0.38%

Total annual operating expenses

rr_ExpensesOverAssets

1.42%

Expenses Deferred Charges [Text Block]

rr_ExpensesDeferredChargesTextBlock

Class A and Class M purchases of $1 million or more will not be subject to a front-end sales charge. Such Class A and Class M purchases may be subject, upon redemption, to a contingent deferred sales charge (CDSC) of 1.00% or 0.25%, respectively.

1 year

rr_ExpenseExampleYear01

$ 489

3 years

rr_ExpenseExampleYear03

784

5 years

rr_ExpenseExampleYear05

1,099

10 years

rr_ExpenseExampleYear10

1,992

1 Year

rr_ExpenseExampleNoRedemptionYear01

489

3 Years

rr_ExpenseExampleNoRedemptionYear03

784

5 Years

rr_ExpenseExampleNoRedemptionYear05

1,099

10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 1,992

02.28 Select Portfolios: Fidelity Advisor Gold Fund - AMCIZ PRO-12 | Gold Portfolio | Fidelity Advisor Gold Fund: Class C

Risk/Return:

rr_RiskReturnAbstract

Maximum sales charge (load) on purchases (as a % of offering price)

rr_MaximumCumulativeSalesChargeOverOfferingPrice

none

Maximum contingent deferred sales charge (as a % of the lesser of original purchase price or redemption proceeds)

rr_MaximumDeferredSalesChargeOverOther

1.00%

^[2]

Management fee

rr_ManagementFeesOverAssets

0.54%

Distribution and/or Service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

1.00%

Other expenses

rr_OtherExpensesOverAssets

0.26%

Total annual operating expenses

rr_ExpensesOverAssets

1.80%

Expenses Deferred Charges [Text Block]

rr_ExpensesDeferredChargesTextBlock

On Class C shares redeemed less than one year after purchase.

1 year

rr_ExpenseExampleYear01

$ 283

3 years

rr_ExpenseExampleYear03

566

5 years

rr_ExpenseExampleYear05

975

10 years

rr_ExpenseExampleYear10

2,116

1 Year

rr_ExpenseExampleNoRedemptionYear01

183

3 Years

rr_ExpenseExampleNoRedemptionYear03

566

5 Years

rr_ExpenseExampleNoRedemptionYear05

975

10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 2,116

02.28 Select Portfolios: Fidelity Advisor Gold Fund - AMCIZ PRO-12 | Gold Portfolio | Fidelity Advisor Gold Fund: Class I

Risk/Return:

rr_RiskReturnAbstract

Maximum sales charge (load) on purchases (as a % of offering price)

rr_MaximumCumulativeSalesChargeOverOfferingPrice

none

Maximum contingent deferred sales charge (as a % of the lesser of original purchase price or redemption proceeds)

rr_MaximumDeferredSalesChargeOverOther

none

Management fee

rr_ManagementFeesOverAssets

0.54%

Distribution and/or Service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

none

Other expenses

rr_OtherExpensesOverAssets

0.25%

Total annual operating expenses

rr_ExpensesOverAssets

0.79%

1 year

rr_ExpenseExampleYear01

$ 81

3 years

rr_ExpenseExampleYear03

252

5 years

rr_ExpenseExampleYear05

439

10 years

rr_ExpenseExampleYear10

978

1 Year

rr_ExpenseExampleNoRedemptionYear01

81

3 Years

rr_ExpenseExampleNoRedemptionYear03

252

5 Years

rr_ExpenseExampleNoRedemptionYear05

439

10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 978

02.28 Select Portfolios: Fidelity Advisor Gold Fund - AMCIZ PRO-12 | Gold Portfolio | Fidelity Advisor Gold Fund: Class Z

Risk/Return:

rr_RiskReturnAbstract

Maximum sales charge (load) on purchases (as a % of offering price)

rr_MaximumCumulativeSalesChargeOverOfferingPrice

none

Maximum contingent deferred sales charge (as a % of the lesser of original purchase price or redemption proceeds)

rr_MaximumDeferredSalesChargeOverOther

none

Management fee

rr_ManagementFeesOverAssets

0.54%

Distribution and/or Service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

none

Other expenses

rr_OtherExpensesOverAssets

0.11%

Total annual operating expenses

rr_ExpensesOverAssets

0.65%

1 year

rr_ExpenseExampleYear01

$ 66

3 years

rr_ExpenseExampleYear03

208

5 years

rr_ExpenseExampleYear05

362

10 years

rr_ExpenseExampleYear10

810

1 Year

rr_ExpenseExampleNoRedemptionYear01

66

3 Years

rr_ExpenseExampleNoRedemptionYear03

208

5 Years

rr_ExpenseExampleNoRedemptionYear05

362

10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 810

02.28 Select Portfolios: Fidelity Advisor Gold Fund - AMCIZ PRO-12 | Gold Portfolio | Return Before Taxes | Fidelity Advisor Gold Fund: Class A

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Gold Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Class A - Return Before Taxes</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

27.29%

Past 5 years

rr_AverageAnnualReturnYear05

7.53%

Past 10 years

rr_AverageAnnualReturnYear10

(4.60%)

02.28 Select Portfolios: Fidelity Advisor Gold Fund - AMCIZ PRO-12 | Gold Portfolio | Return Before Taxes | Fidelity Advisor Gold Fund: Class M

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Gold Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Class M - Return Before Taxes</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

29.92%

Past 5 years

rr_AverageAnnualReturnYear05

7.72%

Past 10 years

rr_AverageAnnualReturnYear10

(4.64%)

02.28 Select Portfolios: Fidelity Advisor Gold Fund - AMCIZ PRO-12 | Gold Portfolio | Return Before Taxes | Fidelity Advisor Gold Fund: Class C

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Gold Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Class C - Return Before Taxes</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

33.09%

Past 5 years

rr_AverageAnnualReturnYear05

8.06%

Past 10 years

rr_AverageAnnualReturnYear10

(4.71%)

02.28 Select Portfolios: Fidelity Advisor Gold Fund - AMCIZ PRO-12 | Gold Portfolio | Return Before Taxes | Fidelity Advisor Gold Fund: Class I

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Gold Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Class I - Return Before Taxes</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

35.50%

Past 5 years

rr_AverageAnnualReturnYear05

9.16%

Past 10 years

rr_AverageAnnualReturnYear10

(3.71%)

02.28 Select Portfolios: Fidelity Advisor Gold Fund - AMCIZ PRO-12 | Gold Portfolio | Return Before Taxes | Fidelity Advisor Gold Fund: Class Z

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Gold Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Class Z - Return Before Taxes</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

35.74%

Past 10 years

rr_AverageAnnualReturnYear10

Since Inception

rr_AverageAnnualReturnSinceInception

36.65%

^[3]

Inception Date

rr_AverageAnnualReturnInceptionDate

Oct. 02, 2018

02.28 Select Portfolios: Fidelity Advisor Gold Fund - AMCIZ PRO-12 | Gold Portfolio | After Taxes on Distributions | Fidelity Advisor Gold Fund: Class A

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Gold Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

27.28%

Past 5 years

rr_AverageAnnualReturnYear05

7.25%

Past 10 years

rr_AverageAnnualReturnYear10

(5.04%)

02.28 Select Portfolios: Fidelity Advisor Gold Fund - AMCIZ PRO-12 | Gold Portfolio | After Taxes on Distributions and Sales | Fidelity Advisor Gold Fund: Class A

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Gold Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions and Sale of Fund Shares</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

16.24%

Past 5 years

rr_AverageAnnualReturnYear05

5.80%

Past 10 years

rr_AverageAnnualReturnYear10

(3.17%)

02.28 Select Portfolios: Fidelity Advisor Gold Fund - AMCIZ PRO-12 | Gold Portfolio | S&P 500® Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

31.49%

Past 5 years

rr_AverageAnnualReturnYear05

11.70%

Past 10 years

rr_AverageAnnualReturnYear10

13.56%

02.28 Select Portfolios: Fidelity Advisor Gold Fund - AMCIZ PRO-12 | Gold Portfolio | S&P® Global BMI Gold Capped 20/45 Linked Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

45.04%

Past 5 years

rr_AverageAnnualReturnYear05

13.19%

Past 10 years

rr_AverageAnnualReturnYear10

(2.52%)

[1] Class A and Class M purchases of $1 million or more will not be subject to a front-end sales charge. Such Class A and Class M purchases may be subject, upon redemption, to a contingent deferred sales charge (CDSC) of 1.00% or 0.25%, respectively.

[2] On Class C shares redeemed less than one year after purchase.

[3] Since inception October 2, 2018.

XML

Total

02.28 Select Portfolios: Group 4 Financials Sector Combo PRO-15 | Financial Services Portfolio

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: bold 12pt Arial, Helvetica, sans-serif;">Fund:<br/>Financial Services Portfolio</p>

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

The fund seeks capital appreciation.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

Shareholder Fees {- Financial Services Portfolio}	02.28 Select Portfolios: Group 4 Financials Sector Combo PRO-15 Financial Services Portfolio USD ($)
(fees paid directly from your investment)	none

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Annual Operating Expenses {- Financial Services Portfolio}	02.28 Select Portfolios: Group 4 Financials Sector Combo PRO-15 Financial Services Portfolio Financial Services Portfolio-Default
Management fee	0.54%
Distribution and/or Service (12b-1) fees	none
Other expenses	0.23%
Total annual operating expenses	0.77%

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Expense Example {- Financial Services Portfolio}	02.28 Select Portfolios: Group 4 Financials Sector Combo PRO-15 Financial Services Portfolio Financial Services Portfolio-Default USD ($)
1 year	$ 79
3 years	246
5 years	428
10 years	$ 954

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 61% of the average value of its portfolio.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in providing financial services to consumers and industry.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Financials Industry Concentration. The financials industries are subject to extensive government regulation, can be subject to relatively rapid change due to increasingly blurred distinctions between service segments, and can be significantly affected by availability and cost of capital funds, changes in interest rates, the rate of corporate and consumer debt defaults, and price competition.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	23.10%	March 31, 2012
Lowest Quarter Return	-23.01%	September 30, 2011
Year-to-Date Return	-34.99%	March 31, 2020

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

Average Annual Total Returns{- Financial Services Portfolio} - 02.28 Select Portfolios: Group 4 Financials Sector Combo PRO-15 - Financial Services Portfolio	Past 1 year	Past 5 years	Past 10 years
Financial Services Portfolio-Default | Return Before Taxes	34.24%	9.27%	9.59%
Financial Services Portfolio-Default | After Taxes on Distributions	32.55%	8.03%	8.85%
Financial Services Portfolio-Default | After Taxes on Distributions and Sales	21.47%	7.15%	7.77%
S&P 500® Index(reflects no deduction for fees, expenses, or taxes)	31.49%	11.70%	13.56%
MSCI US IMI Financials 5% Capped Linked Index(reflects no deduction for fees, expenses, or taxes)	31.39%	10.84%	12.20%

XML

Label

Element

Value

Risk/Return:

rr_RiskReturnAbstract

Registrant Name

dei_EntityRegistrantName

FIDELITY SELECT PORTFOLIOS

Prospectus Date

rr_ProspectusDate

Apr. 29, 2020

02.28 Select Portfolios: Group 4 Financials Sector Combo PRO-15 | Brokerage and Investment Management Portfolio

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: bold 12pt Arial, Helvetica, sans-serif;">Fund:<br/>Brokerage and Investment Management Portfolio</p>

Objective [Heading]

rr_ObjectiveHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks capital appreciation.

Expense [Heading]

rr_ExpenseHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

Shareholder Fees Caption [Text]

rr_ShareholderFeesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

(fees paid directly from your investment)

rr_ShareholderFeeOther

none

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

Portfolio Turnover [Text Block]

rr_PortfolioTurnoverTextBlock

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 9% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

9.00%

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Strategy [Heading]

rr_StrategyHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in the exchange of financial instruments, stock brokerage, commodity brokerage, investment banking, tax-advantaged investment or investment sales, investment management, or related investment advisory and financial decision support services.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

Strategy Portfolio Concentration [Text]

rr_StrategyPortfolioConcentration

<font style="FONT-FAMILY: Times New Roman" size="3">Normally investing at least 80% of assets in securities of companies principally engaged in the exchange of financial instruments, stock brokerage, commodity brokerage, investment banking, tax-advantaged investment or investment sales, investment management, or related investment advisory and financial decision support services.</font>

Risk [Heading]

rr_RiskHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Brokerage and Investment Management Industry Concentration. The brokerage and investment management industry can be significantly affected by stock and bond market activity, changes in regulations, brokerage commission structure, and a competitive environment combined with the high operating leverage inherent in companies in this industry.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

Risk Lose Money [Text]

rr_RiskLoseMoney

<font style="FONT-FAMILY: Times New Roman" size="3">You could lose money by investing in the fund.</font>

Risk Nondiversified Status [Text]

rr_RiskNondiversifiedStatus

<font style="FONT-FAMILY: Times New Roman" size="3">In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.</font>

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

<font style="FONT-FAMILY: Times New Roman" size="3">An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</font>

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

<font style="FONT-FAMILY: Times New Roman" size="3">The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time.</font>

Performance Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

<font style="FONT-FAMILY: Times New Roman" size="3">www.fidelity.com </font>

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

<font style="FONT-FAMILY: Times New Roman" size="3">Past performance (before and after taxes) is not an indication of future performance.</font>

Bar Chart [Heading]

rr_BarChartHeading

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	21.95%	March 31, 2012
Lowest Quarter Return	-23.45%	September 30, 2011
Year-to-Date Return	-20.86%	March 31, 2020

Performance Table Heading

rr_PerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

<font style="FONT-FAMILY: Times New Roman" size="3">After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes.</font>

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

<font style="FONT-FAMILY: Times New Roman" size="3">The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan).</font>

Performance Table Explanation after Tax Higher

rr_PerformanceTableExplanationAfterTaxHigher

<font style="FONT-FAMILY: Times New Roman" size="3">Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.</font>

Performance Table Narrative

rr_PerformanceTableNarrativeTextBlock

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

02.28 Select Portfolios: Group 4 Financials Sector Combo PRO-15 | Brokerage and Investment Management Portfolio | Brokerage and Investment Management Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Management fee

rr_ManagementFeesOverAssets

0.54%

Distribution and/or Service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

none

Other expenses

rr_OtherExpensesOverAssets

0.23%

Total annual operating expenses

rr_ExpensesOverAssets

0.77%

1 year

rr_ExpenseExampleYear01

$ 79

3 years

rr_ExpenseExampleYear03

246

5 years

rr_ExpenseExampleYear05

428

10 years

rr_ExpenseExampleYear10

$ 954

2010

rr_AnnualReturn2010

11.20%

2011

rr_AnnualReturn2011

(22.84%)

2012

rr_AnnualReturn2012

28.31%

2013

rr_AnnualReturn2013

48.87%

2014

rr_AnnualReturn2014

5.24%

2015

rr_AnnualReturn2015

(9.71%)

2016

rr_AnnualReturn2016

6.70%

2017

rr_AnnualReturn2017

29.94%

2018

rr_AnnualReturn2018

(15.02%)

2019

rr_AnnualReturn2019

31.60%

Year to Date Return, Label

rr_YearToDateReturnLabel

Year-to-Date Return

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Mar. 31, 2020

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

(20.86%)

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Highest Quarter Return

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Mar. 31, 2012

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

21.95%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Lowest Quarter Return

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Sep. 30, 2011

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(23.45%)

02.28 Select Portfolios: Group 4 Financials Sector Combo PRO-15 | Brokerage and Investment Management Portfolio | Return Before Taxes | Brokerage and Investment Management Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Brokerage and Investment Management Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return Before Taxes</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

31.60%

Past 5 years

rr_AverageAnnualReturnYear05

6.96%

Past 10 years

rr_AverageAnnualReturnYear10

9.22%

02.28 Select Portfolios: Group 4 Financials Sector Combo PRO-15 | Brokerage and Investment Management Portfolio | After Taxes on Distributions | Brokerage and Investment Management Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Brokerage and Investment Management Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

30.24%

Past 5 years

rr_AverageAnnualReturnYear05

5.54%

Past 10 years

rr_AverageAnnualReturnYear10

8.31%

02.28 Select Portfolios: Group 4 Financials Sector Combo PRO-15 | Brokerage and Investment Management Portfolio | After Taxes on Distributions and Sales | Brokerage and Investment Management Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Brokerage and Investment Management Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions and Sale of Fund Shares</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

19.58%

Past 5 years

rr_AverageAnnualReturnYear05

5.17%

Past 10 years

rr_AverageAnnualReturnYear10

7.38%

02.28 Select Portfolios: Group 4 Financials Sector Combo PRO-15 | Brokerage and Investment Management Portfolio | S&P 500® Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

31.49%

Past 5 years

rr_AverageAnnualReturnYear05

11.70%

Past 10 years

rr_AverageAnnualReturnYear10

13.56%

02.28 Select Portfolios: Group 4 Financials Sector Combo PRO-15 | Brokerage and Investment Management Portfolio | MSCI U.S. IMI Capital Markets 5% Capped Linked Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

31.60%

Past 5 years

rr_AverageAnnualReturnYear05

7.36%

Past 10 years

rr_AverageAnnualReturnYear10

9.83%

XML

Total

02.28 Select Portfolios: Group 7 Information Technology Sector Combo PRO-16 | Technology Portfolio

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: bold 12pt Arial, Helvetica, sans-serif;">Fund:<br/>Technology Portfolio</p>

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

The fund seeks capital appreciation.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

Shareholder Fees {- Technology Portfolio}	02.28 Select Portfolios: Group 7 Information Technology Sector Combo PRO-16 Technology Portfolio USD ($)
(fees paid directly from your investment)	none

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Annual Operating Expenses {- Technology Portfolio}	02.28 Select Portfolios: Group 7 Information Technology Sector Combo PRO-16 Technology Portfolio Technology Portfolio-Default
Management fee	0.54%
Distribution and/or Service (12b-1) fees	none
Other expenses	0.17%
Total annual operating expenses	0.71%

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Expense Example {- Technology Portfolio}	02.28 Select Portfolios: Group 7 Information Technology Sector Combo PRO-16 Technology Portfolio Technology Portfolio-Default USD ($)
1 year	$ 73
3 years	227
5 years	395
10 years	$ 883

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 32% of the average value of its portfolio.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in offering, using, or developing products, processes, or services that will provide or will benefit significantly from technological advances and improvements.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets, particularly emerging markets, can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Technology Industry Concentration. The technology industries can be significantly affected by obsolescence of existing technology, short product cycles, falling prices and profits, competition from new market entrants, and general economic conditions.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	22.17%	March 31, 2012
Lowest Quarter Return	-22.49%	December 31, 2018
Year-to-Date Return	-11.46%	March 31, 2020

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

Average Annual Total Returns{- Technology Portfolio} - 02.28 Select Portfolios: Group 7 Information Technology Sector Combo PRO-16 - Technology Portfolio	Past 1 year	Past 5 years	Past 10 years
Technology Portfolio-Default | Return Before Taxes	51.07%	19.94%	17.13%
Technology Portfolio-Default | After Taxes on Distributions	50.40%	17.64%	15.09%
Technology Portfolio-Default | After Taxes on Distributions and Sales	30.70%	15.45%	13.63%
S&P 500® Index(reflects no deduction for fees, expenses, or taxes)	31.49%	11.70%	13.56%
MSCI U.S. IMI Information Technology 25-50 Index(reflects no deduction for fees, expenses, or taxes)	48.85%	19.53%	17.26%

XML

Total

02.28 Select Portfolios: Group 1 Consumer Discretionary Sector Combo PRO-16 | Automotive Portfolio

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: bold 12pt Arial, Helvetica, sans-serif;">Fund:<br/>Automotive Portfolio</p>

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

The fund seeks capital appreciation.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

Shareholder Fees {- Automotive Portfolio}	02.28 Select Portfolios: Group 1 Consumer Discretionary Sector Combo PRO-16 Automotive Portfolio USD ($)
(fees paid directly from your investment)	none

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Annual Operating Expenses {- Automotive Portfolio}	02.28 Select Portfolios: Group 1 Consumer Discretionary Sector Combo PRO-16 Automotive Portfolio Automotive Portfolio-Default
Management fee	0.54%
Distribution and/or Service (12b-1) fees	none
Other expenses	0.46%
Total annual operating expenses	1.00%

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Expense Example {- Automotive Portfolio}	02.28 Select Portfolios: Group 1 Consumer Discretionary Sector Combo PRO-16 Automotive Portfolio Automotive Portfolio-Default USD ($)
1 year	$ 102
3 years	318
5 years	552
10 years	$ 1,225

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 45% of the average value of its portfolio.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in the manufacture, marketing or sale of automobiles, trucks, specialty vehicles, parts, tires, and related services.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Automotive Industry Concentration. The automotive industry is highly cyclical and can be significantly affected by labor relations and fluctuating component prices.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	25.56%	December 31, 2010
Lowest Quarter Return	-31.64%	September 30, 2011
Year-to-Date Return	-26.87%	March 31, 2020

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

Average Annual Total Returns{- Automotive Portfolio} - 02.28 Select Portfolios: Group 1 Consumer Discretionary Sector Combo PRO-16 - Automotive Portfolio	Past 1 year	Past 5 years	Past 10 years
Automotive Portfolio-Default | Return Before Taxes	28.87%	5.43%	10.34%
Automotive Portfolio-Default | After Taxes on Distributions	27.67%	3.10%	8.29%
Automotive Portfolio-Default | After Taxes on Distributions and Sales	17.95%	3.91%	8.16%
S&P 500® Index(reflects no deduction for fees, expenses, or taxes)	31.49%	11.70%	13.56%
FactSet Automotive Linked Index(reflects no deduction for fees, expenses, or taxes)	26.10%	5.40%	10.59%

XML

Label

Element

Value

Risk/Return:

rr_RiskReturnAbstract

Registrant Name

dei_EntityRegistrantName

FIDELITY SELECT PORTFOLIOS

Prospectus Date

rr_ProspectusDate

Apr. 29, 2020

02.28 Select Portfolios: Group 5 Health Care Sector Combo PRO-13 | Health Care Services Portfolio

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: bold 12pt Arial, Helvetica, sans-serif;">Fund:<br/>Health Care Services Portfolio</p>

Objective [Heading]

rr_ObjectiveHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks capital appreciation.

Expense [Heading]

rr_ExpenseHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

Shareholder Fees Caption [Text]

rr_ShareholderFeesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

(fees paid directly from your investment)

rr_ShareholderFeeOther

none

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

Portfolio Turnover [Text Block]

rr_PortfolioTurnoverTextBlock

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 37% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

37.00%

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Strategy [Heading]

rr_StrategyHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in the ownership or management of hospitals, nursing homes, health maintenance organizations, and other companies specializing in the delivery of health care services.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

Strategy Portfolio Concentration [Text]

rr_StrategyPortfolioConcentration

<font style="FONT-FAMILY: Times New Roman" size="3">Normally investing at least 80% of assets in securities of companies principally engaged in the ownership or management of hospitals, nursing homes, health maintenance organizations, and other companies specializing in the delivery of health care services.</font>

Risk [Heading]

rr_RiskHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Health Care Services Industry Concentration. The health care services industry is subject to extensive government regulation and can be significantly affected by government reimbursement for medical expenses, rising costs of medical products and services, pricing pressure, and an increased emphasis on outpatient services.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

Risk Lose Money [Text]

rr_RiskLoseMoney

<font style="FONT-FAMILY: Times New Roman" size="3">You could lose money by investing in the fund.</font>

Risk Nondiversified Status [Text]

rr_RiskNondiversifiedStatus

<font style="FONT-FAMILY: Times New Roman" size="3">In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.</font>

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

<font style="FONT-FAMILY: Times New Roman" size="3">An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</font>

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

<font style="FONT-FAMILY: Times New Roman" size="3">The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time.</font>

Performance Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

<font style="FONT-FAMILY: Times New Roman" size="3">www.fidelity.com </font>

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

<font style="FONT-FAMILY: Times New Roman" size="3">Past performance (before and after taxes) is not an indication of future performance.</font>

Bar Chart [Heading]

rr_BarChartHeading

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	26.24%	December 31, 2019
Lowest Quarter Return	-17.91%	September 30, 2011
Year-to-Date Return	-13.30%	March 31, 2020

Performance Table Heading

rr_PerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

<font style="FONT-FAMILY: Times New Roman" size="3">After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes.</font>

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

<font style="FONT-FAMILY: Times New Roman" size="3">The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan).</font>

Performance Table Explanation after Tax Higher

rr_PerformanceTableExplanationAfterTaxHigher

<font style="FONT-FAMILY: Times New Roman" size="3">Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.</font>

Performance Table Narrative

rr_PerformanceTableNarrativeTextBlock

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

02.28 Select Portfolios: Group 5 Health Care Sector Combo PRO-13 | Health Care Services Portfolio | Health Care Services Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Management fee

rr_ManagementFeesOverAssets

0.54%

Distribution and/or Service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

none

Other expenses

rr_OtherExpensesOverAssets

0.21%

Total annual operating expenses

rr_ExpensesOverAssets

0.75%

1 year

rr_ExpenseExampleYear01

$ 77

3 years

rr_ExpenseExampleYear03

240

5 years

rr_ExpenseExampleYear05

417

10 years

rr_ExpenseExampleYear10

$ 930

2010

rr_AnnualReturn2010

15.43%

2011

rr_AnnualReturn2011

10.23%

2012

rr_AnnualReturn2012

10.55%

2013

rr_AnnualReturn2013

35.31%

2014

rr_AnnualReturn2014

23.66%

2015

rr_AnnualReturn2015

6.95%

2016

rr_AnnualReturn2016

2.25%

2017

rr_AnnualReturn2017

24.34%

2018

rr_AnnualReturn2018

10.45%

2019

rr_AnnualReturn2019

19.91%

Year to Date Return, Label

rr_YearToDateReturnLabel

Year-to-Date Return

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Mar. 31, 2020

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

(13.30%)

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Highest Quarter Return

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Dec. 31, 2019

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

26.24%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Lowest Quarter Return

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Sep. 30, 2011

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(17.91%)

02.28 Select Portfolios: Group 5 Health Care Sector Combo PRO-13 | Health Care Services Portfolio | Return Before Taxes | Health Care Services Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Health Care Services Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return Before Taxes</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

19.91%

Past 5 years

rr_AverageAnnualReturnYear05

12.48%

Past 10 years

rr_AverageAnnualReturnYear10

15.54%

02.28 Select Portfolios: Group 5 Health Care Sector Combo PRO-13 | Health Care Services Portfolio | After Taxes on Distributions | Health Care Services Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Health Care Services Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

19.83%

Past 5 years

rr_AverageAnnualReturnYear05

10.69%

Past 10 years

rr_AverageAnnualReturnYear10

14.02%

02.28 Select Portfolios: Group 5 Health Care Sector Combo PRO-13 | Health Care Services Portfolio | After Taxes on Distributions and Sales | Health Care Services Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Health Care Services Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions and Sale of Fund Shares</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

11.84%

Past 5 years

rr_AverageAnnualReturnYear05

9.59%

Past 10 years

rr_AverageAnnualReturnYear10

12.70%

02.28 Select Portfolios: Group 5 Health Care Sector Combo PRO-13 | Health Care Services Portfolio | S&P 500® Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

31.49%

Past 5 years

rr_AverageAnnualReturnYear05

11.70%

Past 10 years

rr_AverageAnnualReturnYear10

13.56%

02.28 Select Portfolios: Group 5 Health Care Sector Combo PRO-13 | Health Care Services Portfolio | MSCI U.S. IMI Health Care Providers & Services 25-50 Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

19.38%

Past 5 years

rr_AverageAnnualReturnYear05

11.92%

Past 10 years

rr_AverageAnnualReturnYear10

16.54%

XML

Label

Element

Value

Risk/Return:

rr_RiskReturnAbstract

Registrant Name

dei_EntityRegistrantName

FIDELITY SELECT PORTFOLIOS

Prospectus Date

rr_ProspectusDate

Apr. 29, 2020

02.28 Select Portfolios: Group 5 Health Care Sector Combo PRO-13 | Pharmaceuticals Portfolio

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: bold 12pt Arial, Helvetica, sans-serif;">Fund:<br/>Pharmaceuticals Portfolio</p>

Objective [Heading]

rr_ObjectiveHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks capital appreciation.

Expense [Heading]

rr_ExpenseHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

Shareholder Fees Caption [Text]

rr_ShareholderFeesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

(fees paid directly from your investment)

rr_ShareholderFeeOther

none

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

Portfolio Turnover [Text Block]

rr_PortfolioTurnoverTextBlock

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 52% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

52.00%

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Strategy [Heading]

rr_StrategyHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in companies engaged in the research, development, manufacture, sale, or distribution of pharmaceuticals and drugs of all types.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

Strategy Portfolio Concentration [Text]

rr_StrategyPortfolioConcentration

<font style="FONT-FAMILY: Times New Roman" size="3">Normally investing at least 80% of assets in companies engaged in the research, development, manufacture, sale, or distribution of pharmaceuticals and drugs of all types.</font>

Risk [Heading]

rr_RiskHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Pharmaceuticals Industry Concentration. The pharmaceuticals industry can be significantly affected by government approval of products and services, government regulation and reimbursement rates, patent expirations, and intense competition.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

Risk Lose Money [Text]

rr_RiskLoseMoney

<font style="FONT-FAMILY: Times New Roman" size="3">You could lose money by investing in the fund.</font>

Risk Nondiversified Status [Text]

rr_RiskNondiversifiedStatus

<font style="FONT-FAMILY: Times New Roman" size="3">In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.</font>

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

<font style="FONT-FAMILY: Times New Roman" size="3">An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</font>

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

<font style="FONT-FAMILY: Times New Roman" size="3">The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time.</font>

Performance Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

<font style="FONT-FAMILY: Times New Roman" size="3">www.fidelity.com</font>

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

<font style="FONT-FAMILY: Times New Roman" size="3">Past performance (before and after taxes) is not an indication of future performance.</font>

Bar Chart [Heading]

rr_BarChartHeading

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	17.28%	December 31, 2019
Lowest Quarter Return	-11.62%	March 31, 2016
Year-to-Date Return	-10.00%	March 31, 2020

Performance Table Heading

rr_PerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

<font style="FONT-FAMILY: Times New Roman" size="3">After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes.</font>

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

<font style="FONT-FAMILY: Times New Roman" size="3">The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan).</font>

Performance Table Explanation after Tax Higher

rr_PerformanceTableExplanationAfterTaxHigher

<font style="FONT-FAMILY: Times New Roman" size="3">Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.</font>

Performance Table Narrative

rr_PerformanceTableNarrativeTextBlock

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

02.28 Select Portfolios: Group 5 Health Care Sector Combo PRO-13 | Pharmaceuticals Portfolio | Pharmaceuticals Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Management fee

rr_ManagementFeesOverAssets

0.54%

Distribution and/or Service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

none

Other expenses

rr_OtherExpensesOverAssets

0.24%

Total annual operating expenses

rr_ExpensesOverAssets

0.78%

1 year

rr_ExpenseExampleYear01

$ 80

3 years

rr_ExpenseExampleYear03

249

5 years

rr_ExpenseExampleYear05

433

10 years

rr_ExpenseExampleYear10

$ 966

2010

rr_AnnualReturn2010

16.36%

2011

rr_AnnualReturn2011

13.70%

2012

rr_AnnualReturn2012

14.25%

2013

rr_AnnualReturn2013

41.36%

2014

rr_AnnualReturn2014

23.82%

2015

rr_AnnualReturn2015

8.19%

2016

rr_AnnualReturn2016

(16.27%)

2017

rr_AnnualReturn2017

10.69%

2018

rr_AnnualReturn2018

5.81%

2019

rr_AnnualReturn2019

31.63%

Year to Date Return, Label

rr_YearToDateReturnLabel

Year-to-Date Return

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Mar. 31, 2020

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

(10.00%)

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Highest Quarter Return

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Dec. 31, 2019

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

17.28%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Lowest Quarter Return

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Mar. 31, 2016

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(11.62%)

02.28 Select Portfolios: Group 5 Health Care Sector Combo PRO-13 | Pharmaceuticals Portfolio | Return Before Taxes | Pharmaceuticals Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Pharmaceuticals Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return Before Taxes</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

31.63%

Past 5 years

rr_AverageAnnualReturnYear05

6.91%

Past 10 years

rr_AverageAnnualReturnYear10

13.96%

02.28 Select Portfolios: Group 5 Health Care Sector Combo PRO-13 | Pharmaceuticals Portfolio | After Taxes on Distributions | Pharmaceuticals Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Pharmaceuticals Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

28.96%

Past 5 years

rr_AverageAnnualReturnYear05

5.62%

Past 10 years

rr_AverageAnnualReturnYear10

12.51%

02.28 Select Portfolios: Group 5 Health Care Sector Combo PRO-13 | Pharmaceuticals Portfolio | After Taxes on Distributions and Sales | Pharmaceuticals Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Pharmaceuticals Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions and Sale of Fund Shares</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

20.28%

Past 5 years

rr_AverageAnnualReturnYear05

5.19%

Past 10 years

rr_AverageAnnualReturnYear10

11.37%

02.28 Select Portfolios: Group 5 Health Care Sector Combo PRO-13 | Pharmaceuticals Portfolio | S&P 500® Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

31.49%

Past 5 years

rr_AverageAnnualReturnYear05

11.70%

Past 10 years

rr_AverageAnnualReturnYear10

13.56%

02.28 Select Portfolios: Group 5 Health Care Sector Combo PRO-13 | Pharmaceuticals Portfolio | MSCI North America IMI + ADR Custom Pharmaceuticals 25/50 Linked Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

18.56%

Past 5 years

rr_AverageAnnualReturnYear05

4.80%

Past 10 years

rr_AverageAnnualReturnYear10

12.24%

XML

Total

02.28 Select Portfolios: Group 1 Consumer Discretionary Sector Combo PRO-16 | Consumer Discretionary Portfolio

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: bold 12pt Arial, Helvetica, sans-serif;">Fund:<br/>Consumer Discretionary Portfolio</p>

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

The fund seeks capital appreciation.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

Shareholder Fees {- Consumer Discretionary Portfolio}	02.28 Select Portfolios: Group 1 Consumer Discretionary Sector Combo PRO-16 Consumer Discretionary Portfolio USD ($)
(fees paid directly from your investment)	none

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Annual Operating Expenses {- Consumer Discretionary Portfolio}	02.28 Select Portfolios: Group 1 Consumer Discretionary Sector Combo PRO-16 Consumer Discretionary Portfolio Consumer Discretionary Portfolio-Default
Management fee	0.54%
Distribution and/or Service (12b-1) fees	none
Other expenses	0.22%
Total annual operating expenses	0.76%

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Expense Example {- Consumer Discretionary Portfolio}	02.28 Select Portfolios: Group 1 Consumer Discretionary Sector Combo PRO-16 Consumer Discretionary Portfolio Consumer Discretionary Portfolio-Default USD ($)
1 year	$ 78
3 years	243
5 years	422
10 years	$ 942

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 41% of the average value of its portfolio.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in the manufacture and distribution of consumer discretionary products and services.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Consumer Discretionary Industry Concentration. The consumer discretionary industries can be significantly affected by the performance of the overall economy, interest rates, competition, consumer confidence and spending, and changes in demographics and consumer tastes.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	17.82%	March 31, 2012
Lowest Quarter Return	-15.84%	December 31, 2018
Year-to-Date Return	-21.62%	March 31, 2020

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

Average Annual Total Returns{- Consumer Discretionary Portfolio} - 02.28 Select Portfolios: Group 1 Consumer Discretionary Sector Combo PRO-16 - Consumer Discretionary Portfolio	Past 1 year	Past 5 years	Past 10 years
Consumer Discretionary Portfolio-Default | Return Before Taxes	27.04%	11.07%	15.17%
Consumer Discretionary Portfolio-Default | After Taxes on Distributions	26.35%	10.33%	13.96%
Consumer Discretionary Portfolio-Default | After Taxes on Distributions and Sales	16.45%	8.67%	12.41%
S&P 500® Index(reflects no deduction for fees, expenses, or taxes)	31.49%	11.70%	13.56%
MSCI U.S. IMI Consumer Discretionary 25-50 Index(reflects no deduction for fees, expenses, or taxes)	27.65%	12.09%	16.80%

XML

Total

02.28 Select Portfolios: Group 6 Industrials Sector Combo PRO-10 | Transportation Portfolio

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: bold 12pt Arial, Helvetica, sans-serif;">Fund:<br/>Transportation Portfolio</p>

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

The fund seeks capital appreciation.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

Shareholder Fees {- Transportation Portfolio}	02.28 Select Portfolios: Group 6 Industrials Sector Combo PRO-10 Transportation Portfolio USD ($)
(fees paid directly from your investment)	none

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Annual Operating Expenses {- Transportation Portfolio}	02.28 Select Portfolios: Group 6 Industrials Sector Combo PRO-10 Transportation Portfolio Transportation Portfolio-Default
Management fee	0.53%
Distribution and/or Service (12b-1) fees	none
Other expenses	0.26%
Total annual operating expenses	0.79%

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Expense Example {- Transportation Portfolio}	02.28 Select Portfolios: Group 6 Industrials Sector Combo PRO-10 Transportation Portfolio Transportation Portfolio-Default USD ($)
1 year	$ 81
3 years	252
5 years	439
10 years	$ 978

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 78% of the average value of its portfolio.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

• Normally investing primarily in common stocks.

• Investing in domestic and foreign issuers.

• Normally investing at least 80% of assets in securities of companies principally engaged in providing transportation services or companies principally engaged in the design, manufacture, distribution, or sale of transportation equipment.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Transportation Industry Concentration. The transportation industry can be significantly affected by changes in the economy, fuel prices, labor relations, insurance costs, and government regulation.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	20.72%	March 31, 2010
Lowest Quarter Return	-21.74%	September 30, 2011
Year-to-Date Return	-29.06%	March 31, 2020

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

Average Annual Total Returns{- Transportation Portfolio} - 02.28 Select Portfolios: Group 6 Industrials Sector Combo PRO-10 - Transportation Portfolio	Past 1 year	Past 5 years	Past 10 years
Transportation Portfolio-Default | Return Before Taxes	18.39%	5.74%	14.60%
Transportation Portfolio-Default | After Taxes on Distributions	17.30%	4.32%	13.42%
Transportation Portfolio-Default | After Taxes on Distributions and Sales	11.66%	4.29%	12.11%
S&P 500® Index(reflects no deduction for fees, expenses, or taxes)	31.49%	11.70%	13.56%
MSCI U.S. IMI Transportation 25-50 Index(reflects no deduction for fees, expenses, or taxes)	22.79%	6.15%	14.21%

XML

Label

Element

Value

Risk/Return:

rr_RiskReturnAbstract

Registrant Name

dei_EntityRegistrantName

FIDELITY SELECT PORTFOLIOS

Prospectus Date

rr_ProspectusDate

Apr. 29, 2020

02.28 Select Portfolios: Group 10 Utilities Sector PRO-08 | Utilities Portfolio

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: bold 12pt Arial, Helvetica, sans-serif;">Fund:<br/>Utilities Portfolio</p>

Objective [Heading]

rr_ObjectiveHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks capital appreciation.

Expense [Heading]

rr_ExpenseHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

Shareholder Fees Caption [Text]

rr_ShareholderFeesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

(fees paid directly from your investment)

rr_ShareholderFeeOther

none

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

Portfolio Turnover [Text Block]

rr_PortfolioTurnoverTextBlock

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 65% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

65.00%

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Strategy [Heading]

rr_StrategyHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in the utilities industry and companies deriving a majority of their revenues from their utility operations.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

Strategy Portfolio Concentration [Text]

rr_StrategyPortfolioConcentration

<font style="FONT-FAMILY: Times New Roman" size="3">Normally investing at least 80% of assets in securities of companies principally engaged in the utilities industry and companies deriving a majority of their revenues from their utility operations.</font>

Risk [Heading]

rr_RiskHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Utilities Industry Concentration. The utilities industries can be significantly affected by government regulation, interest rate changes, financing difficulties, supply and demand of services or fuel, intense competition, natural resource conservation, and commodity price fluctuations.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

Risk Lose Money [Text]

rr_RiskLoseMoney

<font style="FONT-FAMILY: Times New Roman" size="3">You could lose money by investing in the fund.</font>

Risk Nondiversified Status [Text]

rr_RiskNondiversifiedStatus

<font style="FONT-FAMILY: Times New Roman" size="3">In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.</font>

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

<font style="FONT-FAMILY: Times New Roman" size="3">An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</font>

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

<font style="FONT-FAMILY: Times New Roman" size="3">The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time.</font>

Performance Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

<font style="FONT-FAMILY: Times New Roman" size="3">www.fidelity.com </font>

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

<font style="FONT-FAMILY: Times New Roman" size="3">Past performance (before and after taxes) is not an indication of future performance.</font>

Bar Chart [Heading]

rr_BarChartHeading

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	14.30%	March 31, 2013
Lowest Quarter Return	-6.41%	June 30, 2015
Year-to-Date Return	-17.71%	March 31, 2020

Performance Table Heading

rr_PerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

<font style="FONT-FAMILY: Times New Roman" size="3">After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes.</font>

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

<font style="FONT-FAMILY: Times New Roman" size="3">The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan).</font>

Performance Table Explanation after Tax Higher

rr_PerformanceTableExplanationAfterTaxHigher

<font style="FONT-FAMILY: Times New Roman" size="3">Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.</font>

Performance Table Narrative

rr_PerformanceTableNarrativeTextBlock

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

02.28 Select Portfolios: Group 10 Utilities Sector PRO-08 | Utilities Portfolio | Utilities Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Management fee

rr_ManagementFeesOverAssets

0.54%

Distribution and/or Service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

none

Other expenses

rr_OtherExpensesOverAssets

0.21%

Total annual operating expenses

rr_ExpensesOverAssets

0.75%

1 year

rr_ExpenseExampleYear01

$ 77

3 years

rr_ExpenseExampleYear03

240

5 years

rr_ExpenseExampleYear05

417

10 years

rr_ExpenseExampleYear10

$ 930

2010

rr_AnnualReturn2010

10.94%

2011

rr_AnnualReturn2011

13.09%

2012

rr_AnnualReturn2012

7.03%

2013

rr_AnnualReturn2013

20.61%

2014

rr_AnnualReturn2014

21.66%

2015

rr_AnnualReturn2015

(10.89%)

2016

rr_AnnualReturn2016

14.00%

2017

rr_AnnualReturn2017

17.96%

2018

rr_AnnualReturn2018

8.58%

2019

rr_AnnualReturn2019

22.66%

Year to Date Return, Label

rr_YearToDateReturnLabel

Year-to-Date Return

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Mar. 31, 2020

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

(17.71%)

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Highest Quarter Return

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Mar. 31, 2013

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

14.30%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Lowest Quarter Return

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Jun. 30, 2015

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(6.41%)

02.28 Select Portfolios: Group 10 Utilities Sector PRO-08 | Utilities Portfolio | Return Before Taxes | Utilities Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Utilities Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return Before Taxes</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

22.66%

Past 5 years

rr_AverageAnnualReturnYear05

9.80%

Past 10 years

rr_AverageAnnualReturnYear10

12.14%

02.28 Select Portfolios: Group 10 Utilities Sector PRO-08 | Utilities Portfolio | After Taxes on Distributions | Utilities Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Utilities Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

22.00%

Past 5 years

rr_AverageAnnualReturnYear05

8.65%

Past 10 years

rr_AverageAnnualReturnYear10

11.18%

02.28 Select Portfolios: Group 10 Utilities Sector PRO-08 | Utilities Portfolio | After Taxes on Distributions and Sales | Utilities Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Utilities Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions and Sale of Fund Shares</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

13.88%

Past 5 years

rr_AverageAnnualReturnYear05

7.55%

Past 10 years

rr_AverageAnnualReturnYear10

9.90%

02.28 Select Portfolios: Group 10 Utilities Sector PRO-08 | Utilities Portfolio | S&P 500® Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

31.49%

Past 5 years

rr_AverageAnnualReturnYear05

11.70%

Past 10 years

rr_AverageAnnualReturnYear10

13.56%

02.28 Select Portfolios: Group 10 Utilities Sector PRO-08 | Utilities Portfolio | MSCI U.S. IMI Utilities 25-50 Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

25.03%

Past 5 years

rr_AverageAnnualReturnYear05

10.50%

Past 10 years

rr_AverageAnnualReturnYear10

12.13%

XML

Total

02.28 Select Portfolios: Group 10 Utilities Sector PRO-08 | Utilities Portfolio

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: bold 12pt Arial, Helvetica, sans-serif;">Fund:<br/>Utilities Portfolio</p>

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

The fund seeks capital appreciation.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

Shareholder Fees {- Utilities Portfolio}	02.28 Select Portfolios: Group 10 Utilities Sector PRO-08 Utilities Portfolio USD ($)
(fees paid directly from your investment)	none

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Annual Operating Expenses {- Utilities Portfolio}	02.28 Select Portfolios: Group 10 Utilities Sector PRO-08 Utilities Portfolio Utilities Portfolio-Default
Management fee	0.54%
Distribution and/or Service (12b-1) fees	none
Other expenses	0.21%
Total annual operating expenses	0.75%

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Expense Example {- Utilities Portfolio}	02.28 Select Portfolios: Group 10 Utilities Sector PRO-08 Utilities Portfolio Utilities Portfolio-Default USD ($)
1 year	$ 77
3 years	240
5 years	417
10 years	$ 930

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 65% of the average value of its portfolio.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in the utilities industry and companies deriving a majority of their revenues from their utility operations.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Utilities Industry Concentration. The utilities industries can be significantly affected by government regulation, interest rate changes, financing difficulties, supply and demand of services or fuel, intense competition, natural resource conservation, and commodity price fluctuations.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	14.30%	March 31, 2013
Lowest Quarter Return	-6.41%	June 30, 2015
Year-to-Date Return	-17.71%	March 31, 2020

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

Average Annual Total Returns{- Utilities Portfolio} - 02.28 Select Portfolios: Group 10 Utilities Sector PRO-08 - Utilities Portfolio	Past 1 year	Past 5 years	Past 10 years
Utilities Portfolio-Default | Return Before Taxes	22.66%	9.80%	12.14%
Utilities Portfolio-Default | After Taxes on Distributions	22.00%	8.65%	11.18%
Utilities Portfolio-Default | After Taxes on Distributions and Sales	13.88%	7.55%	9.90%
S&P 500® Index(reflects no deduction for fees, expenses, or taxes)	31.49%	11.70%	13.56%
MSCI U.S. IMI Utilities 25-50 Index(reflects no deduction for fees, expenses, or taxes)	25.03%	10.50%	12.13%

XML

Label

Element

Value

Risk/Return:

rr_RiskReturnAbstract

Registrant Name

dei_EntityRegistrantName

FIDELITY SELECT PORTFOLIOS

Prospectus Date

rr_ProspectusDate

Apr. 29, 2020

02.28 Select Portfolios: Group 1 Consumer Discretionary Sector Combo PRO-16 | Automotive Portfolio

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: bold 12pt Arial, Helvetica, sans-serif;">Fund:<br/>Automotive Portfolio</p>

Objective [Heading]

rr_ObjectiveHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks capital appreciation.

Expense [Heading]

rr_ExpenseHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

Shareholder Fees Caption [Text]

rr_ShareholderFeesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

(fees paid directly from your investment)

rr_ShareholderFeeOther

none

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

Portfolio Turnover [Text Block]

rr_PortfolioTurnoverTextBlock

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 45% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

45.00%

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Strategy [Heading]

rr_StrategyHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in the manufacture, marketing or sale of automobiles, trucks, specialty vehicles, parts, tires, and related services.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

Strategy Portfolio Concentration [Text]

rr_StrategyPortfolioConcentration

<font style="FONT-FAMILY: Times New Roman" size="3">Normally investing at least 80% of assets in securities of companies principally engaged in the manufacture, marketing or sale of automobiles, trucks, specialty vehicles, parts, tires, and related services.</font>

Risk [Heading]

rr_RiskHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Automotive Industry Concentration. The automotive industry is highly cyclical and can be significantly affected by labor relations and fluctuating component prices.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

Risk Lose Money [Text]

rr_RiskLoseMoney

<font style="FONT-FAMILY: Times New Roman" size="3">You could lose money by investing in the fund.</font>

Risk Nondiversified Status [Text]

rr_RiskNondiversifiedStatus

<font style="FONT-FAMILY: Times New Roman" size="3">In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.</font>

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

<font style="FONT-FAMILY: Times New Roman" size="3">An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</font>

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

<font style="FONT-FAMILY: Times New Roman" size="3">The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time.</font>

Performance Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

<font style="FONT-FAMILY: Times New Roman" size="3">www.fidelity.com </font>

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

<font style="FONT-FAMILY: Times New Roman" size="3">Past performance (before and after taxes) is not an indication of future performance.</font>

Bar Chart [Heading]

rr_BarChartHeading

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	25.56%	December 31, 2010
Lowest Quarter Return	-31.64%	September 30, 2011
Year-to-Date Return	-26.87%	March 31, 2020

Performance Table Heading

rr_PerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

<font style="FONT-FAMILY: Times New Roman" size="3">After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes.</font>

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

<font style="FONT-FAMILY: Times New Roman" size="3">The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan).</font>

Performance Table Explanation after Tax Higher

rr_PerformanceTableExplanationAfterTaxHigher

<font style="FONT-FAMILY: Times New Roman" size="3">Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.</font>

Performance Table Narrative

rr_PerformanceTableNarrativeTextBlock

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

02.28 Select Portfolios: Group 1 Consumer Discretionary Sector Combo PRO-16 | Automotive Portfolio | Automotive Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Management fee

rr_ManagementFeesOverAssets

0.54%

Distribution and/or Service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

none

Other expenses

rr_OtherExpensesOverAssets

0.46%

Total annual operating expenses

rr_ExpensesOverAssets

1.00%

1 year

rr_ExpenseExampleYear01

$ 102

3 years

rr_ExpenseExampleYear03

318

5 years

rr_ExpenseExampleYear05

552

10 years

rr_ExpenseExampleYear10

$ 1,225

2010

rr_AnnualReturn2010

46.18%

2011

rr_AnnualReturn2011

(26.16%)

2012

rr_AnnualReturn2012

26.17%

2013

rr_AnnualReturn2013

46.67%

2014

rr_AnnualReturn2014

2.79%

2015

rr_AnnualReturn2015

0.17%

2016

rr_AnnualReturn2016

(5.83%)

2017

rr_AnnualReturn2017

23.95%

2018

rr_AnnualReturn2018

(13.54%)

2019

rr_AnnualReturn2019

28.87%

Year to Date Return, Label

rr_YearToDateReturnLabel

Year-to-Date Return

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Mar. 31, 2020

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

(26.87%)

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Highest Quarter Return

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Dec. 31, 2010

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

25.56%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Lowest Quarter Return

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Sep. 30, 2011

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(31.64%)

02.28 Select Portfolios: Group 1 Consumer Discretionary Sector Combo PRO-16 | Automotive Portfolio | Return Before Taxes | Automotive Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Automotive Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return Before Taxes</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

28.87%

Past 5 years

rr_AverageAnnualReturnYear05

5.43%

Past 10 years

rr_AverageAnnualReturnYear10

10.34%

02.28 Select Portfolios: Group 1 Consumer Discretionary Sector Combo PRO-16 | Automotive Portfolio | After Taxes on Distributions | Automotive Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Automotive Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

27.67%

Past 5 years

rr_AverageAnnualReturnYear05

3.10%

Past 10 years

rr_AverageAnnualReturnYear10

8.29%

02.28 Select Portfolios: Group 1 Consumer Discretionary Sector Combo PRO-16 | Automotive Portfolio | After Taxes on Distributions and Sales | Automotive Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Automotive Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions and Sale of Fund Shares</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

17.95%

Past 5 years

rr_AverageAnnualReturnYear05

3.91%

Past 10 years

rr_AverageAnnualReturnYear10

8.16%

02.28 Select Portfolios: Group 1 Consumer Discretionary Sector Combo PRO-16 | Automotive Portfolio | S&P 500® Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

31.49%

Past 5 years

rr_AverageAnnualReturnYear05

11.70%

Past 10 years

rr_AverageAnnualReturnYear10

13.56%

02.28 Select Portfolios: Group 1 Consumer Discretionary Sector Combo PRO-16 | Automotive Portfolio | FactSet Automotive Linked Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

26.10%

Past 5 years

rr_AverageAnnualReturnYear05

5.40%

Past 10 years

rr_AverageAnnualReturnYear10

10.59%

XML

Label

Element

Value

Risk/Return:

rr_RiskReturnAbstract

Registrant Name

dei_EntityRegistrantName

FIDELITY SELECT PORTFOLIOS

Prospectus Date

rr_ProspectusDate

Apr. 29, 2020

02.28 Select Portfolios: Group 5 Health Care Sector Combo PRO-13 | Health Care Portfolio

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: bold 12pt Arial, Helvetica, sans-serif;">Fund:<br/>Health Care Portfolio</p>

Objective [Heading]

rr_ObjectiveHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks capital appreciation.

Expense [Heading]

rr_ExpenseHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

Shareholder Fees Caption [Text]

rr_ShareholderFeesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

(fees paid directly from your investment)

rr_ShareholderFeeOther

none

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

Portfolio Turnover [Text Block]

rr_PortfolioTurnoverTextBlock

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 36% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

36.00%

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Strategy [Heading]

rr_StrategyHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in the design, manufacture, or sale of products or services used for or in connection with health care or medicine.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

Strategy Portfolio Concentration [Text]

rr_StrategyPortfolioConcentration

<font style="FONT-FAMILY: Times New Roman" size="3">Normally investing at least 80% of assets in securities of companies principally engaged in the design, manufacture, or sale of products or services used for or in connection with health care or medicine.</font>

Risk [Heading]

rr_RiskHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Health Care Industry Concentration. The health care industries are subject to government regulation and reimbursement rates, as well as government approval of products and services, which could have a significant effect on price and availability, and can be significantly affected by product liability claims, rapid obsolescence, and patent expirations.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

Risk Lose Money [Text]

rr_RiskLoseMoney

<font style="FONT-FAMILY: Times New Roman" size="3">You could lose money by investing in the fund.</font>

Risk Nondiversified Status [Text]

rr_RiskNondiversifiedStatus

<font style="FONT-FAMILY: Times New Roman" size="3">In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.</font>

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

<font style="FONT-FAMILY: Times New Roman" size="3">An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</font>

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

<font style="FONT-FAMILY: Times New Roman" size="3">The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time.</font>

Performance Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

<font style="FONT-FAMILY: Times New Roman" size="3">www.fidelity.com</font>

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

<font style="FONT-FAMILY: Times New Roman" size="3">Past performance (before and after taxes) is not an indication of future performance.</font>

Bar Chart [Heading]

rr_BarChartHeading

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	22.15%	December 31, 2019
Lowest Quarter Return	-15.01%	December 31, 2018
Year-to-Date Return	-11.05%	March 31, 2020

Performance Table Heading

rr_PerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

<font style="FONT-FAMILY: Times New Roman" size="3">After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes.</font>

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

<font style="FONT-FAMILY: Times New Roman" size="3">The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan).</font>

Performance Table Explanation after Tax Higher

rr_PerformanceTableExplanationAfterTaxHigher

<font style="FONT-FAMILY: Times New Roman" size="3">Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.</font>

Performance Table Narrative

rr_PerformanceTableNarrativeTextBlock

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

02.28 Select Portfolios: Group 5 Health Care Sector Combo PRO-13 | Health Care Portfolio | Health Care Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Management fee

rr_ManagementFeesOverAssets

0.54%

Distribution and/or Service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

none

Other expenses

rr_OtherExpensesOverAssets

0.16%

Total annual operating expenses

rr_ExpensesOverAssets

0.70%

1 year

rr_ExpenseExampleYear01

$ 72

3 years

rr_ExpenseExampleYear03

224

5 years

rr_ExpenseExampleYear05

390

10 years

rr_ExpenseExampleYear10

$ 871

2010

rr_AnnualReturn2010

16.96%

2011

rr_AnnualReturn2011

7.82%

2012

rr_AnnualReturn2012

21.39%

2013

rr_AnnualReturn2013

56.27%

2014

rr_AnnualReturn2014

32.88%

2015

rr_AnnualReturn2015

6.57%

2016

rr_AnnualReturn2016

(10.68%)

2017

rr_AnnualReturn2017

24.02%

2018

rr_AnnualReturn2018

7.44%

2019

rr_AnnualReturn2019

31.46%

Year to Date Return, Label

rr_YearToDateReturnLabel

Year-to-Date Return

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Mar. 31, 2020

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

(11.05%)

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Highest Quarter Return

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Dec. 31, 2019

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

22.15%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Lowest Quarter Return

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Dec. 31, 2018

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(15.01%)

02.28 Select Portfolios: Group 5 Health Care Sector Combo PRO-13 | Health Care Portfolio | Return Before Taxes | Health Care Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Health Care Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return Before Taxes</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

31.46%

Past 5 years

rr_AverageAnnualReturnYear05

10.77%

Past 10 years

rr_AverageAnnualReturnYear10

18.15%

02.28 Select Portfolios: Group 5 Health Care Sector Combo PRO-13 | Health Care Portfolio | After Taxes on Distributions | Health Care Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Health Care Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

31.04%

Past 5 years

rr_AverageAnnualReturnYear05

9.42%

Past 10 years

rr_AverageAnnualReturnYear10

16.30%

02.28 Select Portfolios: Group 5 Health Care Sector Combo PRO-13 | Health Care Portfolio | After Taxes on Distributions and Sales | Health Care Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Health Care Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions and Sale of Fund Shares</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

18.92%

Past 5 years

rr_AverageAnnualReturnYear05

8.17%

Past 10 years

rr_AverageAnnualReturnYear10

14.80%

02.28 Select Portfolios: Group 5 Health Care Sector Combo PRO-13 | Health Care Portfolio | S&P 500® Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

31.49%

Past 5 years

rr_AverageAnnualReturnYear05

11.70%

Past 10 years

rr_AverageAnnualReturnYear10

13.56%

02.28 Select Portfolios: Group 5 Health Care Sector Combo PRO-13 | Health Care Portfolio | MSCI U.S. IMI Health Care 25-50 Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

22.03%

Past 5 years

rr_AverageAnnualReturnYear05

10.54%

Past 10 years

rr_AverageAnnualReturnYear10

15.26%

XML

Total

02.28 Select Portfolios: Group 1 Consumer Discretionary Sector Combo PRO-16 | Construction and Housing Portfolio

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: bold 12pt Arial, Helvetica, sans-serif;">Fund:<br/>Construction and Housing Portfolio</p>

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

The fund seeks capital appreciation.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

Shareholder Fees {- Construction and Housing Portfolio}	02.28 Select Portfolios: Group 1 Consumer Discretionary Sector Combo PRO-16 Construction and Housing Portfolio USD ($)
(fees paid directly from your investment)	none

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Annual Operating Expenses {- Construction and Housing Portfolio}	02.28 Select Portfolios: Group 1 Consumer Discretionary Sector Combo PRO-16 Construction and Housing Portfolio Construction and Housing Portfolio-Default
Management fee	0.54%
Distribution and/or Service (12b-1) fees	none
Other expenses	0.25%
Total annual operating expenses	0.79%

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Expense Example {- Construction and Housing Portfolio}	02.28 Select Portfolios: Group 1 Consumer Discretionary Sector Combo PRO-16 Construction and Housing Portfolio Construction and Housing Portfolio-Default USD ($)
1 year	$ 81
3 years	252
5 years	439
10 years	$ 978

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 161% of the average value of its portfolio.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in the design and construction of residential, commercial, industrial, and public works facilities, as well as companies engaged in the manufacture, supply, distribution, or sale of construction and housing products or services.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Construction and Housing Industry Concentration. The construction and housing industry can be significantly affected by changes in housing starts, the level of new and existing home sales, government spending, public works, interest rates, consumer confidence and spending, taxation, and demographic patterns.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

• High Portfolio Turnover. High portfolio turnover (more than 100%) may result in increased transaction costs and potentially higher capital gains or losses. The effects of higher than normal portfolio turnover may adversely affect the fund's performance.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	24.65%	December 31, 2011
Lowest Quarter Return	-19.41%	September 30, 2011
Year-to-Date Return	-25.74%	March 31, 2020

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

Average Annual Total Returns{- Construction and Housing Portfolio} - 02.28 Select Portfolios: Group 1 Consumer Discretionary Sector Combo PRO-16 - Construction and Housing Portfolio	Past 1 year	Past 5 years	Past 10 years
Construction and Housing Portfolio-Default | Return Before Taxes	41.07%	11.02%	15.11%
Construction and Housing Portfolio-Default | After Taxes on Distributions	38.10%	8.82%	13.38%
Construction and Housing Portfolio-Default | After Taxes on Distributions and Sales	25.67%	8.35%	12.36%
S&P 500® Index(reflects no deduction for fees, expenses, or taxes)	31.49%	11.70%	13.56%
MSCI U.S. IMI Construction & Housing 25-50 Index(reflects no deduction for fees, expenses, or taxes)	36.61%	12.90%	15.82%

XML

Label

Element

Value

Risk/Return:

rr_RiskReturnAbstract

Registrant Name

dei_EntityRegistrantName

FIDELITY SELECT PORTFOLIOS

Prospectus Date

rr_ProspectusDate

Apr. 29, 2020

02.28 Select Portfolios: Fidelity Advisor Communication Services Fund - AMCIZ PRO-03 | Communication Services Portfolio

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: normal 12pt Arial, Helvetica, sans-serif;"><b>Fund/Class</b>:<br/><b>Communication Services Portfolio</b>/Fidelity Advisor® Communication Services Fund A, M, C, I, Z</p>

Objective [Heading]

rr_ObjectiveHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks capital appreciation.

Expense [Heading]

rr_ExpenseHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund. In addition to the fees and expenses described below, your broker may also require you to pay brokerage commissions on purchases and sales of certain share classes of the fund.

You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $50,000 in the fund or certain other Fidelity^® funds. More information about these and other discounts is available from your investment professional and in the "Fund Distribution" section beginning on page 28 of the prospectus. Different intermediaries may provide additional waivers or reductions of the sales charge. Please see “Sales Charge Waiver Policies Applied by Certain Intermediaries” in the “Appendix” section of the prospectus.

Shareholder Fees Caption [Text]

rr_ShareholderFeesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(fees paid directly from your investment)</p>

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

Portfolio Turnover [Text Block]

rr_PortfolioTurnoverTextBlock

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 73% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

73.00%

Expense Breakpoint Discounts [Text]

rr_ExpenseBreakpointDiscounts

<font style="FONT-FAMILY: Times New Roman" size="3">You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $50,000 in the fund or certain other Fidelity® funds. More information about these and other discounts is available from your investment professional and in the "Fund Distribution" section beginning on page 28 of the prospectus.</font>

Expense Breakpoint, Minimum Investment Required [Amount]

rr_ExpenseBreakpointMinimumInvestmentRequiredAmount

$ 50,000

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated and if you hold your shares:

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Expense Example, No Redemption, By Year, Caption [Text]

rr_ExpenseExampleNoRedemptionByYearCaption

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Hold Shares</p>

Strategy [Heading]

rr_StrategyHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in the development, production, or distribution of communication services.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

Strategy Portfolio Concentration [Text]

rr_StrategyPortfolioConcentration

<font style="FONT-FAMILY: Times New Roman" size="3">Normally investing at least 80% of assets in securities of companies principally engaged in the development, production, or distribution of communication services.</font>

Risk [Heading]

rr_RiskHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Communication Services Concentration. The communication services industries can be significantly affected by government regulation, intense competition, technology changes, general economic conditions, consumer and business confidence and spending, and changes in consumer and business preferences.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

Risk Lose Money [Text]

rr_RiskLoseMoney

<font style="FONT-FAMILY: Times New Roman" size="3">You could lose money by investing in the fund.</font>

Risk Nondiversified Status [Text]

rr_RiskNondiversifiedStatus

<font style="FONT-FAMILY: Times New Roman" size="3">In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.</font>

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

<font style="FONT-FAMILY: Times New Roman" size="3">An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</font>

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the performance of the fund's shares over the past year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Prior to December 1, 2018, the fund was named Multimedia Portfolio, and the fund operated under certain different investment policies and compared its performance to a different additional index. The fund's historical performance may not represent its current investment policies.

Visit institutional.fidelity.com for more recent performance information.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

<font style="FONT-FAMILY: Times New Roman" size="3">The information illustrates the performance of the fund's shares over the past year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time.</font>

Performance Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

<font style="FONT-FAMILY: Times New Roman" size="3">institutional.fidelity.com </font>

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

<font style="FONT-FAMILY: Times New Roman" size="3">Past performance (before and after taxes) is not an indication of future performance.</font>

Bar Chart [Heading]

rr_BarChartHeading

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

Bar Chart Narrative [Text Block]

rr_BarChartNarrativeTextBlock

The returns in the bar chart do not reflect any applicable sales charges; if sales charges were reflected, returns would be lower than those shown.

Bar Chart Does Not Reflect Sales Loads [Text]

rr_BarChartDoesNotReflectSalesLoads

<font style="FONT-FAMILY: Times New Roman" size="3">The returns in the bar chart do not reflect any applicable sales charges; if sales charges were reflected, returns would be lower than those shown.</font>

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

During the periods shown in the chart for Class A:	Returns	Quarter ended
Highest Quarter Return	15.44%	March 31, 2019
Lowest Quarter Return	0.78%	September 30, 2019
Year-to-Date Return	-16.80%	March 31, 2020

Performance Table Heading

rr_PerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

Performance Table Does Reflect Sales Loads

rr_PerformanceTableDoesReflectSalesLoads

<font style="FONT-FAMILY: Times New Roman" size="3">Unlike the returns in the bar chart, the returns in the table reflect the maximum applicable sales charges.</font>

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

<font style="FONT-FAMILY: Times New Roman" size="3">After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes.</font>

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

<font style="FONT-FAMILY: Times New Roman" size="3">The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan).</font>

Performance Table One Class of after Tax Shown [Text]

rr_PerformanceTableOneClassOfAfterTaxShown

<font style="FONT-FAMILY: Times New Roman" size="3">After-tax returns for Class A are shown in the table below and after-tax returns for other classes will vary</font>

Performance Table Explanation after Tax Higher

rr_PerformanceTableExplanationAfterTaxHigher

<font style="FONT-FAMILY: Times New Roman" size="3">Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.</font>

Performance Table Narrative

rr_PerformanceTableNarrativeTextBlock

Unlike the returns in the bar chart, the returns in the table reflect the maximum applicable sales charges. After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. After-tax returns for Class A are shown in the table below and after-tax returns for other classes will vary. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

02.28 Select Portfolios: Fidelity Advisor Communication Services Fund - AMCIZ PRO-03 | Communication Services Portfolio | Fidelity Advisor Communication Services Fund Class A

Risk/Return:

rr_RiskReturnAbstract

Maximum sales charge (load) on purchases (as a % of offering price)

rr_MaximumCumulativeSalesChargeOverOfferingPrice

5.75%

Maximum contingent deferred sales charge (as a % of the lesser of original purchase price or redemption proceeds)

rr_MaximumDeferredSalesChargeOverOther

none

^[1]

Management fee

rr_ManagementFeesOverAssets

0.54%

Distribution and/or Service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

0.25%

Other expenses

rr_OtherExpensesOverAssets

0.28%

Total annual operating expenses

rr_ExpensesOverAssets

1.07%

Expenses Deferred Charges [Text Block]

rr_ExpensesDeferredChargesTextBlock

Class A and Class M purchases of $1 million or more will not be subject to a front-end sales charge. Such Class A and Class M purchases may be subject, upon redemption, to a contingent deferred sales charge (CDSC) of 1.00% or 0.25%, respectively.

1 year

rr_ExpenseExampleYear01

$ 678

3 years

rr_ExpenseExampleYear03

896

5 years

rr_ExpenseExampleYear05

1,131

10 years

rr_ExpenseExampleYear10

1,806

1 Year

rr_ExpenseExampleNoRedemptionYear01

678

3 Years

rr_ExpenseExampleNoRedemptionYear03

896

5 Years

rr_ExpenseExampleNoRedemptionYear05

1,131

10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 1,806

2019

rr_AnnualReturn2019

32.26%

Year to Date Return, Label

rr_YearToDateReturnLabel

Year-to-Date Return

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Mar. 31, 2020

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

(16.80%)

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Highest Quarter Return

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Mar. 31, 2019

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

15.44%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Lowest Quarter Return

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Sep. 30, 2019

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

0.78%

Inception Date

rr_AverageAnnualReturnInceptionDate

Nov. 28, 2018

02.28 Select Portfolios: Fidelity Advisor Communication Services Fund - AMCIZ PRO-03 | Communication Services Portfolio | Fidelity Advisor Communication Services Fund Class M

Risk/Return:

rr_RiskReturnAbstract

Maximum sales charge (load) on purchases (as a % of offering price)

rr_MaximumCumulativeSalesChargeOverOfferingPrice

3.50%

Maximum contingent deferred sales charge (as a % of the lesser of original purchase price or redemption proceeds)

rr_MaximumDeferredSalesChargeOverOther

none

^[1]

Management fee

rr_ManagementFeesOverAssets

0.54%

Distribution and/or Service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

0.50%

Other expenses

rr_OtherExpensesOverAssets

0.31%

Total annual operating expenses

rr_ExpensesOverAssets

1.35%

Expenses Deferred Charges [Text Block]

rr_ExpensesDeferredChargesTextBlock

Class A and Class M purchases of $1 million or more will not be subject to a front-end sales charge. Such Class A and Class M purchases may be subject, upon redemption, to a contingent deferred sales charge (CDSC) of 1.00% or 0.25%, respectively.

1 year

rr_ExpenseExampleYear01

$ 483

3 years

rr_ExpenseExampleYear03

763

5 years

rr_ExpenseExampleYear05

1,063

10 years

rr_ExpenseExampleYear10

1,917

1 Year

rr_ExpenseExampleNoRedemptionYear01

483

3 Years

rr_ExpenseExampleNoRedemptionYear03

763

5 Years

rr_ExpenseExampleNoRedemptionYear05

1,063

10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 1,917

Inception Date

rr_AverageAnnualReturnInceptionDate

Nov. 28, 2018

02.28 Select Portfolios: Fidelity Advisor Communication Services Fund - AMCIZ PRO-03 | Communication Services Portfolio | Fidelity Advisor Communication Services Fund Class C

Risk/Return:

rr_RiskReturnAbstract

Maximum sales charge (load) on purchases (as a % of offering price)

rr_MaximumCumulativeSalesChargeOverOfferingPrice

none

Maximum contingent deferred sales charge (as a % of the lesser of original purchase price or redemption proceeds)

rr_MaximumDeferredSalesChargeOverOther

1.00%

^[2]

Management fee

rr_ManagementFeesOverAssets

0.54%

Distribution and/or Service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

1.00%

Other expenses

rr_OtherExpensesOverAssets

0.32%

Total annual operating expenses

rr_ExpensesOverAssets

1.86%

Expenses Deferred Charges [Text Block]

rr_ExpensesDeferredChargesTextBlock

On Class C shares redeemed less than one year after purchase.

1 year

rr_ExpenseExampleYear01

$ 289

3 years

rr_ExpenseExampleYear03

585

5 years

rr_ExpenseExampleYear05

1,006

10 years

rr_ExpenseExampleYear10

2,180

1 Year

rr_ExpenseExampleNoRedemptionYear01

189

3 Years

rr_ExpenseExampleNoRedemptionYear03

585

5 Years

rr_ExpenseExampleNoRedemptionYear05

1,006

10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 2,180

Inception Date

rr_AverageAnnualReturnInceptionDate

Nov. 28, 2018

02.28 Select Portfolios: Fidelity Advisor Communication Services Fund - AMCIZ PRO-03 | Communication Services Portfolio | Fidelity Advisor Communication Services Fund Class I

Risk/Return:

rr_RiskReturnAbstract

Maximum sales charge (load) on purchases (as a % of offering price)

rr_MaximumCumulativeSalesChargeOverOfferingPrice

none

Maximum contingent deferred sales charge (as a % of the lesser of original purchase price or redemption proceeds)

rr_MaximumDeferredSalesChargeOverOther

none

Management fee

rr_ManagementFeesOverAssets

0.54%

Distribution and/or Service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

none

Other expenses

rr_OtherExpensesOverAssets

0.23%

Total annual operating expenses

rr_ExpensesOverAssets

0.77%

1 year

rr_ExpenseExampleYear01

$ 79

3 years

rr_ExpenseExampleYear03

246

5 years

rr_ExpenseExampleYear05

428

10 years

rr_ExpenseExampleYear10

954

1 Year

rr_ExpenseExampleNoRedemptionYear01

79

3 Years

rr_ExpenseExampleNoRedemptionYear03

246

5 Years

rr_ExpenseExampleNoRedemptionYear05

428

10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 954

Inception Date

rr_AverageAnnualReturnInceptionDate

Nov. 28, 2018

02.28 Select Portfolios: Fidelity Advisor Communication Services Fund - AMCIZ PRO-03 | Communication Services Portfolio | Fidelity Advisor Communication Services Fund Class Z

Risk/Return:

rr_RiskReturnAbstract

Maximum sales charge (load) on purchases (as a % of offering price)

rr_MaximumCumulativeSalesChargeOverOfferingPrice

none

Maximum contingent deferred sales charge (as a % of the lesser of original purchase price or redemption proceeds)

rr_MaximumDeferredSalesChargeOverOther

none

Management fee

rr_ManagementFeesOverAssets

0.54%

Distribution and/or Service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

none

Other expenses

rr_OtherExpensesOverAssets

0.11%

Total annual operating expenses

rr_ExpensesOverAssets

0.65%

1 year

rr_ExpenseExampleYear01

$ 66

3 years

rr_ExpenseExampleYear03

208

5 years

rr_ExpenseExampleYear05

362

10 years

rr_ExpenseExampleYear10

810

1 Year

rr_ExpenseExampleNoRedemptionYear01

66

3 Years

rr_ExpenseExampleNoRedemptionYear03

208

5 Years

rr_ExpenseExampleNoRedemptionYear05

362

10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 810

Inception Date

rr_AverageAnnualReturnInceptionDate

Nov. 28, 2018

02.28 Select Portfolios: Fidelity Advisor Communication Services Fund - AMCIZ PRO-03 | Communication Services Portfolio | Return Before Taxes | Fidelity Advisor Communication Services Fund Class A

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Communication Services Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Class A - Return Before Taxes</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

24.65%

Since Inception

rr_AverageAnnualReturnSinceInception

14.26%

^[3]

02.28 Select Portfolios: Fidelity Advisor Communication Services Fund - AMCIZ PRO-03 | Communication Services Portfolio | Return Before Taxes | Fidelity Advisor Communication Services Fund Class M

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Communication Services Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Class M - Return Before Taxes</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

27.30%

Since Inception

rr_AverageAnnualReturnSinceInception

16.46%

^[3]

02.28 Select Portfolios: Fidelity Advisor Communication Services Fund - AMCIZ PRO-03 | Communication Services Portfolio | Return Before Taxes | Fidelity Advisor Communication Services Fund Class C

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Communication Services Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Class C - Return Before Taxes</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

30.26%

Since Inception

rr_AverageAnnualReturnSinceInception

19.73%

^[3]

02.28 Select Portfolios: Fidelity Advisor Communication Services Fund - AMCIZ PRO-03 | Communication Services Portfolio | Return Before Taxes | Fidelity Advisor Communication Services Fund Class I

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Communication Services Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Class I - Return Before Taxes</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

32.66%

Since Inception

rr_AverageAnnualReturnSinceInception

21.03%

^[3]

02.28 Select Portfolios: Fidelity Advisor Communication Services Fund - AMCIZ PRO-03 | Communication Services Portfolio | Return Before Taxes | Fidelity Advisor Communication Services Fund Class Z

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Communication Services Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Class Z - Return Before Taxes</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

32.82%

Since Inception

rr_AverageAnnualReturnSinceInception

21.18%

^[3]

02.28 Select Portfolios: Fidelity Advisor Communication Services Fund - AMCIZ PRO-03 | Communication Services Portfolio | After Taxes on Distributions | Fidelity Advisor Communication Services Fund Class A

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Communication Services Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

15.95%

Since Inception

rr_AverageAnnualReturnSinceInception

5.04%

^[3]

Inception Date

rr_AverageAnnualReturnInceptionDate

Nov. 28, 2018

02.28 Select Portfolios: Fidelity Advisor Communication Services Fund - AMCIZ PRO-03 | Communication Services Portfolio | After Taxes on Distributions and Sales | Fidelity Advisor Communication Services Fund Class A

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Communication Services Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions and Sale of Fund Shares</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

19.70%

Since Inception

rr_AverageAnnualReturnSinceInception

10.02%

^[3]

Inception Date

rr_AverageAnnualReturnInceptionDate

Nov. 28, 2018

02.28 Select Portfolios: Fidelity Advisor Communication Services Fund - AMCIZ PRO-03 | Communication Services Portfolio | S&P 500® Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

31.49%

Since Inception

rr_AverageAnnualReturnSinceInception

17.98%

^[3]

02.28 Select Portfolios: Fidelity Advisor Communication Services Fund - AMCIZ PRO-03 | Communication Services Portfolio | MSCI U.S. IMI Communication Services 25-50 (Media Linked) Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

27.94%

Since Inception

rr_AverageAnnualReturnSinceInception

15.99%

^[3]

[1] Class A and Class M purchases of $1 million or more will not be subject to a front-end sales charge. Such Class A and Class M purchases may be subject, upon redemption, to a contingent deferred sales charge (CDSC) of 1.00% or 0.25%, respectively.

[2] On Class C shares redeemed less than one year after purchase.

[3] From November 28, 2018

XML

Total

02.28 Select Portfolios: Group 3 Energy Sector Combo PRO-13 | Energy Service Portfolio

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: bold 12pt Arial, Helvetica, sans-serif;">Fund:<br/>Energy Service Portfolio</p>

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

The fund seeks capital appreciation.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

Shareholder Fees {- Energy Service Portfolio}	02.28 Select Portfolios: Group 3 Energy Sector Combo PRO-13 Energy Service Portfolio USD ($)
(fees paid directly from your investment)	none

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Annual Operating Expenses {- Energy Service Portfolio}	02.28 Select Portfolios: Group 3 Energy Sector Combo PRO-13 Energy Service Portfolio Energy Service Portfolio-Default
Management fee	0.53%
Distribution and/or Service (12b-1) fees	none
Other expenses	0.37%
Total annual operating expenses	0.90%

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Expense Example {- Energy Service Portfolio}	02.28 Select Portfolios: Group 3 Energy Sector Combo PRO-13 Energy Service Portfolio Energy Service Portfolio-Default USD ($)
1 year	$ 92
3 years	287
5 years	498
10 years	$ 1,108

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 42% of the average value of its portfolio.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in the energy service field, including those that provide services and equipment to the conventional areas of oil, gas, electricity, and coal, and newer sources of energy such as nuclear, geothermal, oil shale, and solar power.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Energy Service Industry Concentration. The energy service industry can be significantly affected by the supply of and demand for specific equipment or services, the supply of and demand for oil and gas, the price of oil and gas, exploration and production spending, government regulation, world events, and economic conditions.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	26.52%	December 31, 2010
Lowest Quarter Return	-43.87%	December 31, 2018
Year-to-Date Return	-66.31%	March 31, 2020

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

Average Annual Total Returns{- Energy Service Portfolio} - 02.28 Select Portfolios: Group 3 Energy Sector Combo PRO-13 - Energy Service Portfolio	Past 1 year	Past 5 years	Past 10 years
Energy Service Portfolio-Default | Return Before Taxes	0.31%	(13.22%)	(5.87%)
Energy Service Portfolio-Default | After Taxes on Distributions	(0.23%)	(13.80%)	(6.48%)
Energy Service Portfolio-Default | After Taxes on Distributions and Sales	0.49%	(9.26%)	(3.88%)
S&P 500® Index(reflects no deduction for fees, expenses, or taxes)	31.49%	11.70%	13.56%
MSCI U.S. IMI Energy Equipment & Services 25-50 Index(reflects no deduction for fees, expenses, or taxes)	(1.12%)	(15.08%)	(6.16%)

XML

Label

Element

Value

Risk/Return:

rr_RiskReturnAbstract

Registrant Name

dei_EntityRegistrantName

FIDELITY SELECT PORTFOLIOS

Prospectus Date

rr_ProspectusDate

Apr. 29, 2020

02.28 Select Portfolios: Group 4 Financials Sector Combo PRO-15 | Financial Services Portfolio

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: bold 12pt Arial, Helvetica, sans-serif;">Fund:<br/>Financial Services Portfolio</p>

Objective [Heading]

rr_ObjectiveHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks capital appreciation.

Expense [Heading]

rr_ExpenseHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

Shareholder Fees Caption [Text]

rr_ShareholderFeesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

(fees paid directly from your investment)

rr_ShareholderFeeOther

none

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

Portfolio Turnover [Text Block]

rr_PortfolioTurnoverTextBlock

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 61% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

61.00%

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Strategy [Heading]

rr_StrategyHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in providing financial services to consumers and industry.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

Strategy Portfolio Concentration [Text]

rr_StrategyPortfolioConcentration

<font style="FONT-FAMILY: Times New Roman" size="3">Normally investing at least 80% of assets in securities of companies principally engaged in providing financial services to consumers and industry.</font>

Risk [Heading]

rr_RiskHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Financials Industry Concentration. The financials industries are subject to extensive government regulation, can be subject to relatively rapid change due to increasingly blurred distinctions between service segments, and can be significantly affected by availability and cost of capital funds, changes in interest rates, the rate of corporate and consumer debt defaults, and price competition.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

Risk Lose Money [Text]

rr_RiskLoseMoney

<font style="FONT-FAMILY: Times New Roman" size="3">You could lose money by investing in the fund.</font>

Risk Nondiversified Status [Text]

rr_RiskNondiversifiedStatus

<font style="FONT-FAMILY: Times New Roman" size="3">In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.</font>

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

<font style="FONT-FAMILY: Times New Roman" size="3">An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</font>

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

<font style="FONT-FAMILY: Times New Roman" size="3">The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time.</font>

Performance Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

<font style="FONT-FAMILY: Times New Roman" size="3">www.fidelity.com </font>

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

<font style="FONT-FAMILY: Times New Roman" size="3">Past performance (before and after taxes) is not an indication of future performance.</font>

Bar Chart [Heading]

rr_BarChartHeading

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	23.10%	March 31, 2012
Lowest Quarter Return	-23.01%	September 30, 2011
Year-to-Date Return	-34.99%	March 31, 2020

Performance Table Heading

rr_PerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

<font style="FONT-FAMILY: Times New Roman" size="3">After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes.</font>

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

<font style="FONT-FAMILY: Times New Roman" size="3">The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan).</font>

Performance Table Explanation after Tax Higher

rr_PerformanceTableExplanationAfterTaxHigher

<font style="FONT-FAMILY: Times New Roman" size="3">Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.</font>

Performance Table Narrative

rr_PerformanceTableNarrativeTextBlock

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

02.28 Select Portfolios: Group 4 Financials Sector Combo PRO-15 | Financial Services Portfolio | Financial Services Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Management fee

rr_ManagementFeesOverAssets

0.54%

Distribution and/or Service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

none

Other expenses

rr_OtherExpensesOverAssets

0.23%

Total annual operating expenses

rr_ExpensesOverAssets

0.77%

1 year

rr_ExpenseExampleYear01

$ 79

3 years

rr_ExpenseExampleYear03

246

5 years

rr_ExpenseExampleYear05

428

10 years

rr_ExpenseExampleYear10

$ 954

2010

rr_AnnualReturn2010

6.48%

2011

rr_AnnualReturn2011

(20.35%)

2012

rr_AnnualReturn2012

27.81%

2013

rr_AnnualReturn2013

33.67%

2014

rr_AnnualReturn2014

10.73%

2015

rr_AnnualReturn2015

(3.91%)

2016

rr_AnnualReturn2016

18.67%

2017

rr_AnnualReturn2017

20.94%

2018

rr_AnnualReturn2018

(15.86%)

2019

rr_AnnualReturn2019

34.24%

Year to Date Return, Label

rr_YearToDateReturnLabel

Year-to-Date Return

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Mar. 31, 2020

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

(34.99%)

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Highest Quarter Return

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Mar. 31, 2012

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

23.10%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Lowest Quarter Return

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Sep. 30, 2011

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(23.01%)

02.28 Select Portfolios: Group 4 Financials Sector Combo PRO-15 | Financial Services Portfolio | Return Before Taxes | Financial Services Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Financial Services Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return Before Taxes</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

34.24%

Past 5 years

rr_AverageAnnualReturnYear05

9.27%

Past 10 years

rr_AverageAnnualReturnYear10

9.59%

02.28 Select Portfolios: Group 4 Financials Sector Combo PRO-15 | Financial Services Portfolio | After Taxes on Distributions | Financial Services Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Financial Services Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

32.55%

Past 5 years

rr_AverageAnnualReturnYear05

8.03%

Past 10 years

rr_AverageAnnualReturnYear10

8.85%

02.28 Select Portfolios: Group 4 Financials Sector Combo PRO-15 | Financial Services Portfolio | After Taxes on Distributions and Sales | Financial Services Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Financial Services Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions and Sale of Fund Shares</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

21.47%

Past 5 years

rr_AverageAnnualReturnYear05

7.15%

Past 10 years

rr_AverageAnnualReturnYear10

7.77%

02.28 Select Portfolios: Group 4 Financials Sector Combo PRO-15 | Financial Services Portfolio | S&P 500® Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

31.49%

Past 5 years

rr_AverageAnnualReturnYear05

11.70%

Past 10 years

rr_AverageAnnualReturnYear10

13.56%

02.28 Select Portfolios: Group 4 Financials Sector Combo PRO-15 | Financial Services Portfolio | MSCI US IMI Financials 5% Capped Linked Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

31.39%

Past 5 years

rr_AverageAnnualReturnYear05

10.84%

Past 10 years

rr_AverageAnnualReturnYear10

12.20%

XML

Label

Element

Value

Risk/Return:

rr_RiskReturnAbstract

Registrant Name

dei_EntityRegistrantName

FIDELITY SELECT PORTFOLIOS

Prospectus Date

rr_ProspectusDate

Apr. 29, 2020

02.28 Select Portfolios: Group 4 Financials Sector Combo PRO-15 | Banking Portfolio

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: bold 12pt Arial, Helvetica, sans-serif;">Fund:<br/>Banking Portfolio</p>

Objective [Heading]

rr_ObjectiveHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks capital appreciation.

Expense [Heading]

rr_ExpenseHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

Shareholder Fees Caption [Text]

rr_ShareholderFeesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

(fees paid directly from your investment)

rr_ShareholderFeeOther

none

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

Portfolio Turnover [Text Block]

rr_PortfolioTurnoverTextBlock

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 31% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

31.00%

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Strategy [Heading]

rr_StrategyHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in banking.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

Strategy Portfolio Concentration [Text]

rr_StrategyPortfolioConcentration

<font style="FONT-FAMILY: Times New Roman" size="3">Normally investing at least 80% of assets in securities of companies principally engaged in banking.</font>

Risk [Heading]

rr_RiskHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Banking Industry Concentration. The banking industry can be significantly affected by legislation, regulation, competition and by changes in general economic conditions and interest rates.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

Risk Lose Money [Text]

rr_RiskLoseMoney

<font style="FONT-FAMILY: Times New Roman" size="3">You could lose money by investing in the fund.</font>

Risk Nondiversified Status [Text]

rr_RiskNondiversifiedStatus

<font style="FONT-FAMILY: Times New Roman" size="3">In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.</font>

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

<font style="FONT-FAMILY: Times New Roman" size="3">An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</font>

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

<font style="FONT-FAMILY: Times New Roman" size="3">The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time.</font>

Performance Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

<font style="FONT-FAMILY: Times New Roman" size="3">www.fidelity.com </font>

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

<font style="FONT-FAMILY: Times New Roman" size="3">Past performance (before and after taxes) is not an indication of future performance.</font>

Bar Chart [Heading]

rr_BarChartHeading

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	27.24%	December 31, 2016
Lowest Quarter Return	-22.08%	September 30, 2011
Year-to-Date Return	-43.51%	March 31, 2020

Performance Table Heading

rr_PerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

<font style="FONT-FAMILY: Times New Roman" size="3">After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes.</font>

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

<font style="FONT-FAMILY: Times New Roman" size="3">The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan).</font>

Performance Table Explanation after Tax Higher

rr_PerformanceTableExplanationAfterTaxHigher

<font style="FONT-FAMILY: Times New Roman" size="3">Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.</font>

Performance Table Narrative

rr_PerformanceTableNarrativeTextBlock

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

02.28 Select Portfolios: Group 4 Financials Sector Combo PRO-15 | Banking Portfolio | Banking Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Management fee

rr_ManagementFeesOverAssets

0.54%

Distribution and/or Service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

none

Other expenses

rr_OtherExpensesOverAssets

0.23%

Total annual operating expenses

rr_ExpensesOverAssets

0.77%

1 year

rr_ExpenseExampleYear01

$ 79

3 years

rr_ExpenseExampleYear03

246

5 years

rr_ExpenseExampleYear05

428

10 years

rr_ExpenseExampleYear10

$ 954

2010

rr_AnnualReturn2010

21.44%

2011

rr_AnnualReturn2011

(13.31%)

2012

rr_AnnualReturn2012

22.42%

2013

rr_AnnualReturn2013

39.38%

2014

rr_AnnualReturn2014

7.58%

2015

rr_AnnualReturn2015

0.65%

2016

rr_AnnualReturn2016

26.84%

2017

rr_AnnualReturn2017

12.68%

2018

rr_AnnualReturn2018

(18.28%)

2019

rr_AnnualReturn2019

35.59%

Year to Date Return, Label

rr_YearToDateReturnLabel

Year-to-Date Return

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Mar. 31, 2020

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

(43.51%)

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Highest Quarter Return

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Dec. 31, 2016

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

27.24%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Lowest Quarter Return

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Sep. 30, 2011

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(22.08%)

02.28 Select Portfolios: Group 4 Financials Sector Combo PRO-15 | Banking Portfolio | Return Before Taxes | Banking Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Banking Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return Before Taxes</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

35.59%

Past 5 years

rr_AverageAnnualReturnYear05

9.77%

Past 10 years

rr_AverageAnnualReturnYear10

11.91%

02.28 Select Portfolios: Group 4 Financials Sector Combo PRO-15 | Banking Portfolio | After Taxes on Distributions | Banking Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Banking Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

33.68%

Past 5 years

rr_AverageAnnualReturnYear05

7.72%

Past 10 years

rr_AverageAnnualReturnYear10

10.62%

02.28 Select Portfolios: Group 4 Financials Sector Combo PRO-15 | Banking Portfolio | After Taxes on Distributions and Sales | Banking Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Banking Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions and Sale of Fund Shares</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

22.31%

Past 5 years

rr_AverageAnnualReturnYear05

7.42%

Past 10 years

rr_AverageAnnualReturnYear10

9.69%

02.28 Select Portfolios: Group 4 Financials Sector Combo PRO-15 | Banking Portfolio | S&P 500® Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

31.49%

Past 5 years

rr_AverageAnnualReturnYear05

11.70%

Past 10 years

rr_AverageAnnualReturnYear10

13.56%

02.28 Select Portfolios: Group 4 Financials Sector Combo PRO-15 | Banking Portfolio | MSCI US IMI Banks 5% Capped Linked Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

30.77%

Past 5 years

rr_AverageAnnualReturnYear05

10.67%

Past 10 years

rr_AverageAnnualReturnYear10

12.41%

XML

Label

Element

Value

Risk/Return:

rr_RiskReturnAbstract

Registrant Name

dei_EntityRegistrantName

FIDELITY SELECT PORTFOLIOS

Prospectus Date

rr_ProspectusDate

Apr. 29, 2020

02.28 Select Portfolios: Group 3 Energy Sector Combo PRO-13 | Energy Service Portfolio

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: bold 12pt Arial, Helvetica, sans-serif;">Fund:<br/>Energy Service Portfolio</p>

Objective [Heading]

rr_ObjectiveHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks capital appreciation.

Expense [Heading]

rr_ExpenseHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

Shareholder Fees Caption [Text]

rr_ShareholderFeesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

(fees paid directly from your investment)

rr_ShareholderFeeOther

none

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

Portfolio Turnover [Text Block]

rr_PortfolioTurnoverTextBlock

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 42% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

42.00%

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Strategy [Heading]

rr_StrategyHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in the energy service field, including those that provide services and equipment to the conventional areas of oil, gas, electricity, and coal, and newer sources of energy such as nuclear, geothermal, oil shale, and solar power.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

Strategy Portfolio Concentration [Text]

rr_StrategyPortfolioConcentration

<font style="FONT-FAMILY: Times New Roman" size="3">Normally investing at least 80% of assets in securities of companies principally engaged in the energy service field, including those that provide services and equipment to the conventional areas of oil, gas, electricity, and coal, and newer sources of energy such as nuclear, geothermal, oil shale, and solar power.</font>

Risk [Heading]

rr_RiskHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Energy Service Industry Concentration. The energy service industry can be significantly affected by the supply of and demand for specific equipment or services, the supply of and demand for oil and gas, the price of oil and gas, exploration and production spending, government regulation, world events, and economic conditions.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

Risk Lose Money [Text]

rr_RiskLoseMoney

<font style="FONT-FAMILY: Times New Roman" size="3">You could lose money by investing in the fund.</font>

Risk Nondiversified Status [Text]

rr_RiskNondiversifiedStatus

<font style="FONT-FAMILY: Times New Roman" size="3">In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.</font>

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

<font style="FONT-FAMILY: Times New Roman" size="3">An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</font>

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

<font style="FONT-FAMILY: Times New Roman" size="3">The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time.</font>

Performance Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

<font style="FONT-FAMILY: Times New Roman" size="3">www.fidelity.com </font>

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

<font style="FONT-FAMILY: Times New Roman" size="3">Past performance (before and after taxes) is not an indication of future performance.</font>

Bar Chart [Heading]

rr_BarChartHeading

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	26.52%	December 31, 2010
Lowest Quarter Return	-43.87%	December 31, 2018
Year-to-Date Return	-66.31%	March 31, 2020

Performance Table Heading

rr_PerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

<font style="FONT-FAMILY: Times New Roman" size="3">After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes.</font>

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

<font style="FONT-FAMILY: Times New Roman" size="3">The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan).</font>

Performance Table Explanation after Tax Higher

rr_PerformanceTableExplanationAfterTaxHigher

<font style="FONT-FAMILY: Times New Roman" size="3">Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.</font>

Performance Table Narrative

rr_PerformanceTableNarrativeTextBlock

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

02.28 Select Portfolios: Group 3 Energy Sector Combo PRO-13 | Energy Service Portfolio | Energy Service Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Management fee

rr_ManagementFeesOverAssets

0.53%

Distribution and/or Service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

none

Other expenses

rr_OtherExpensesOverAssets

0.37%

Total annual operating expenses

rr_ExpensesOverAssets

0.90%

1 year

rr_ExpenseExampleYear01

$ 92

3 years

rr_ExpenseExampleYear03

287

5 years

rr_ExpenseExampleYear05

498

10 years

rr_ExpenseExampleYear10

$ 1,108

2010

rr_AnnualReturn2010

27.92%

2011

rr_AnnualReturn2011

(12.56%)

2012

rr_AnnualReturn2012

2.57%

2013

rr_AnnualReturn2013

27.48%

2014

rr_AnnualReturn2014

(24.13%)

2015

rr_AnnualReturn2015

(26.41%)

2016

rr_AnnualReturn2016

36.57%

2017

rr_AnnualReturn2017

(12.68%)

2018

rr_AnnualReturn2018

(44.10%)

2019

rr_AnnualReturn2019

0.31%

Year to Date Return, Label

rr_YearToDateReturnLabel

Year-to-Date Return

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Mar. 31, 2020

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

(66.31%)

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Highest Quarter Return

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Dec. 31, 2010

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

26.52%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Lowest Quarter Return

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Dec. 31, 2018

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(43.87%)

02.28 Select Portfolios: Group 3 Energy Sector Combo PRO-13 | Energy Service Portfolio | Return Before Taxes | Energy Service Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Energy Service Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return Before Taxes</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

0.31%

Past 5 years

rr_AverageAnnualReturnYear05

(13.22%)

Past 10 years

rr_AverageAnnualReturnYear10

(5.87%)

02.28 Select Portfolios: Group 3 Energy Sector Combo PRO-13 | Energy Service Portfolio | After Taxes on Distributions | Energy Service Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Energy Service Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

(0.23%)

Past 5 years

rr_AverageAnnualReturnYear05

(13.80%)

Past 10 years

rr_AverageAnnualReturnYear10

(6.48%)

02.28 Select Portfolios: Group 3 Energy Sector Combo PRO-13 | Energy Service Portfolio | After Taxes on Distributions and Sales | Energy Service Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Energy Service Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions and Sale of Fund Shares</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

0.49%

Past 5 years

rr_AverageAnnualReturnYear05

(9.26%)

Past 10 years

rr_AverageAnnualReturnYear10

(3.88%)

02.28 Select Portfolios: Group 3 Energy Sector Combo PRO-13 | Energy Service Portfolio | S&P 500® Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

31.49%

Past 5 years

rr_AverageAnnualReturnYear05

11.70%

Past 10 years

rr_AverageAnnualReturnYear10

13.56%

02.28 Select Portfolios: Group 3 Energy Sector Combo PRO-13 | Energy Service Portfolio | MSCI U.S. IMI Energy Equipment & Services 25-50 Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

(1.12%)

Past 5 years

rr_AverageAnnualReturnYear05

(15.08%)

Past 10 years

rr_AverageAnnualReturnYear10

(6.16%)

XML

Label

Element

Value

Risk/Return:

rr_RiskReturnAbstract

Registrant Name

dei_EntityRegistrantName

FIDELITY SELECT PORTFOLIOS

Prospectus Date

rr_ProspectusDate

Apr. 29, 2020

02.28 Select Portfolios: Group 9 Telecommunications Services Sector Retail Combo PRO-13 | Telecommunications Portfolio

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: normal 12pt Arial, Helvetica, sans-serif;"><b>Fund/Class</b>:<br/><b>Telecommunications Portfolio</b>/Telecommunications Portfolio</p>

Objective [Heading]

rr_ObjectiveHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks capital appreciation.

Expense [Heading]

rr_ExpenseHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

Shareholder Fees Caption [Text]

rr_ShareholderFeesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

(fees paid directly from your investment)

rr_ShareholderFeeOther

none

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

Portfolio Turnover [Text Block]

rr_PortfolioTurnoverTextBlock

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 58% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

58.00%

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Strategy [Heading]

rr_StrategyHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in the development, production, or distribution of telecommunications services.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

Strategy Portfolio Concentration [Text]

rr_StrategyPortfolioConcentration

<font style="FONT-FAMILY: Times New Roman" size="3">Normally investing at least 80% of assets in securities of companies principally engaged in the development, production, or distribution of telecommunications services.</font>

Risk [Heading]

rr_RiskHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Telecom Services Industry Concentration. The telecom services industry is subject to government regulation and can be significantly affected by intense competition and technology changes.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

Risk Lose Money [Text]

rr_RiskLoseMoney

<font style="FONT-FAMILY: Times New Roman" size="3">You could lose money by investing in the fund.</font>

Risk Nondiversified Status [Text]

rr_RiskNondiversifiedStatus

<font style="FONT-FAMILY: Times New Roman" size="3">In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.</font>

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

<font style="FONT-FAMILY: Times New Roman" size="3">An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</font>

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

<font style="FONT-FAMILY: Times New Roman" size="3">The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time.</font>

Performance Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

<font style="FONT-FAMILY: Times New Roman" size="3">www.fidelity.com </font>

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

<font style="FONT-FAMILY: Times New Roman" size="3">Past performance (before and after taxes) is not an indication of future performance.</font>

Bar Chart [Heading]

rr_BarChartHeading

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	17.58%	September 30, 2010
Lowest Quarter Return	-16.97%	September 30, 2011
Year-to-Date Return	-8.13%	March 31, 2020

Performance Table Heading

rr_PerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

<font style="FONT-FAMILY: Times New Roman" size="3">After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes.</font>

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

<font style="FONT-FAMILY: Times New Roman" size="3">The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan).</font>

Performance Table Explanation after Tax Higher

rr_PerformanceTableExplanationAfterTaxHigher

<font style="FONT-FAMILY: Times New Roman" size="3">Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.</font>

Performance Table Narrative

rr_PerformanceTableNarrativeTextBlock

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

02.28 Select Portfolios: Group 9 Telecommunications Services Sector Retail Combo PRO-13 | Telecommunications Portfolio | Telecommunications Portfolio

Risk/Return:

rr_RiskReturnAbstract

Management fee

rr_ManagementFeesOverAssets

0.54%

Distribution and/or Service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

none

Other expenses

rr_OtherExpensesOverAssets

0.29%

Total annual operating expenses

rr_ExpensesOverAssets

0.83%

1 year

rr_ExpenseExampleYear01

$ 85

3 years

rr_ExpenseExampleYear03

265

5 years

rr_ExpenseExampleYear05

460

10 years

rr_ExpenseExampleYear10

$ 1,025

2010

rr_AnnualReturn2010

18.32%

2011

rr_AnnualReturn2011

(4.24%)

2012

rr_AnnualReturn2012

18.64%

2013

rr_AnnualReturn2013

21.52%

2014

rr_AnnualReturn2014

3.61%

2015

rr_AnnualReturn2015

2.31%

2016

rr_AnnualReturn2016

22.81%

2017

rr_AnnualReturn2017

1.69%

2018

rr_AnnualReturn2018

(8.02%)

2019

rr_AnnualReturn2019

20.40%

Year to Date Return, Label

rr_YearToDateReturnLabel

Year-to-Date Return

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Mar. 31, 2020

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

(8.13%)

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Highest Quarter Return

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Sep. 30, 2010

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

17.58%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Lowest Quarter Return

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Sep. 30, 2011

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(16.97%)

02.28 Select Portfolios: Group 9 Telecommunications Services Sector Retail Combo PRO-13 | Telecommunications Portfolio | Return Before Taxes | Telecommunications Portfolio

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Telecommunications Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return Before Taxes</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

20.40%

Past 5 years

rr_AverageAnnualReturnYear05

7.19%

Past 10 years

rr_AverageAnnualReturnYear10

9.13%

02.28 Select Portfolios: Group 9 Telecommunications Services Sector Retail Combo PRO-13 | Telecommunications Portfolio | After Taxes on Distributions | Telecommunications Portfolio

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Telecommunications Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

19.46%

Past 5 years

rr_AverageAnnualReturnYear05

5.46%

Past 10 years

rr_AverageAnnualReturnYear10

8.00%

02.28 Select Portfolios: Group 9 Telecommunications Services Sector Retail Combo PRO-13 | Telecommunications Portfolio | After Taxes on Distributions and Sales | Telecommunications Portfolio

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Telecommunications Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions and Sale of Fund Shares</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

12.73%

Past 5 years

rr_AverageAnnualReturnYear05

5.40%

Past 10 years

rr_AverageAnnualReturnYear10

7.32%

02.28 Select Portfolios: Group 9 Telecommunications Services Sector Retail Combo PRO-13 | Telecommunications Portfolio | S&P 500® Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

31.49%

Past 5 years

rr_AverageAnnualReturnYear05

11.70%

Past 10 years

rr_AverageAnnualReturnYear10

13.56%

02.28 Select Portfolios: Group 9 Telecommunications Services Sector Retail Combo PRO-13 | Telecommunications Portfolio | MSCI U.S. IM Telecommunication Services 25-50 Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

12.64%

Past 5 years

rr_AverageAnnualReturnYear05

4.11%

Past 10 years

rr_AverageAnnualReturnYear10

7.99%

XML

Label

Element

Value

Risk/Return:

rr_RiskReturnAbstract

Registrant Name

dei_EntityRegistrantName

FIDELITY SELECT PORTFOLIOS

Prospectus Date

rr_ProspectusDate

Apr. 29, 2020

02.28 Select Portfolios: Fidelity Advisor Materials Fund - AMCIZ PRO-12 | Materials Portfolio

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: normal 12pt Arial, Helvetica, sans-serif;"><b>Fund/Class</b>:<br/><b>Materials Portfolio</b>/Fidelity Advisor® Materials Fund A, M, C, I, Z</p>

Objective [Heading]

rr_ObjectiveHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks capital appreciation.

Expense [Heading]

rr_ExpenseHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund. In addition to the fees and expenses described below, your broker may also require you to pay brokerage commissions on purchases and sales of certain share classes of the fund.

You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $50,000 in the fund or certain other Fidelity^® funds. More information about these and other discounts is available from your investment professional and in the "Fund Distribution" section beginning on page 28 of the prospectus. Different intermediaries may provide additional waivers or reductions of the sales charge. Please see “Sales Charge Waiver Policies Applied by Certain Intermediaries” in the “Appendix” section of the prospectus.

Shareholder Fees Caption [Text]

rr_ShareholderFeesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(fees paid directly from your investment)</p>

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

Portfolio Turnover [Text Block]

rr_PortfolioTurnoverTextBlock

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 69% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

69.00%

Expense Breakpoint Discounts [Text]

rr_ExpenseBreakpointDiscounts

<font style="FONT-FAMILY: Times New Roman" size="3">You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $50,000 in the fund or certain other Fidelity® funds. More information about these and other discounts is available from your investment professional and in the "Fund Distribution" section beginning on page 28 of the prospectus.</font>

Expense Breakpoint, Minimum Investment Required [Amount]

rr_ExpenseBreakpointMinimumInvestmentRequiredAmount

$ 50,000

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated and if you hold your shares:

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Expense Example, No Redemption, By Year, Caption [Text]

rr_ExpenseExampleNoRedemptionByYearCaption

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Hold Shares</p>

Strategy [Heading]

rr_StrategyHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in the manufacture, mining, processing, or distribution of raw materials and intermediate goods.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

Strategy Portfolio Concentration [Text]

rr_StrategyPortfolioConcentration

<font style="FONT-FAMILY: Times New Roman" size="3">Normally investing at least 80% of assets in securities of companies principally engaged in the manufacture, mining, processing, or distribution of raw materials and intermediate goods.</font>

Risk [Heading]

rr_RiskHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Materials Industry Concentration. The materials industries can be significantly affected by the level and volatility of commodity prices, the exchange value of the dollar, import and export controls, worldwide competition, liability for environmental damage, depletion of resources, and mandated expenditures for safety and pollution control.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

Risk Lose Money [Text]

rr_RiskLoseMoney

<font style="FONT-FAMILY: Times New Roman" size="3">You could lose money by investing in the fund.</font>

Risk Nondiversified Status [Text]

rr_RiskNondiversifiedStatus

<font style="FONT-FAMILY: Times New Roman" size="3">In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.</font>

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

<font style="FONT-FAMILY: Times New Roman" size="3">An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</font>

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit institutional.fidelity.com for more recent performance information.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

<font style="FONT-FAMILY: Times New Roman" size="3">The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time.</font>

Performance Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

<font style="FONT-FAMILY: Times New Roman" size="3">institutional.fidelity.com</font>

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

<font style="FONT-FAMILY: Times New Roman" size="3">Past performance (before and after taxes) is not an indication of future performance.</font>

Bar Chart [Heading]

rr_BarChartHeading

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

Bar Chart Narrative [Text Block]

rr_BarChartNarrativeTextBlock

The returns in the bar chart do not reflect any applicable sales charges; if sales charges were reflected, returns would be lower than those shown.

Bar Chart Does Not Reflect Sales Loads [Text]

rr_BarChartDoesNotReflectSalesLoads

<font style="FONT-FAMILY: Times New Roman" size="3">The returns in the bar chart do not reflect any applicable sales charges; if sales charges were reflected, returns would be lower than those shown.</font>

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

During the periods shown in the chart for Class A:	Returns	Quarter ended
Highest Quarter Return	20.81%	December 31, 2010
Lowest Quarter Return	-25.35%	September 30, 2011
Year-to-Date Return	-26.36%	March 31, 2020

Performance Table Heading

rr_PerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

Performance Table Does Reflect Sales Loads

rr_PerformanceTableDoesReflectSalesLoads

<font style="FONT-FAMILY: Times New Roman" size="3">Unlike the returns in the bar chart, the returns in the table reflect the maximum applicable sales charges.</font>

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

<font style="FONT-FAMILY: Times New Roman" size="3">After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes.</font>

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

<font style="FONT-FAMILY: Times New Roman" size="3">The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan).</font>

Performance Table One Class of after Tax Shown [Text]

rr_PerformanceTableOneClassOfAfterTaxShown

<font style="FONT-FAMILY: Times New Roman" size="3">After-tax returns for Class A are shown in the table below and after-tax returns for other classes will vary.</font>

Performance Table Explanation after Tax Higher

rr_PerformanceTableExplanationAfterTaxHigher

<font style="FONT-FAMILY: Times New Roman" size="3">Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.</font>

Performance Table Narrative

rr_PerformanceTableNarrativeTextBlock

Unlike the returns in the bar chart, the returns in the table reflect the maximum applicable sales charges. After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. After-tax returns for Class A are shown in the table below and after-tax returns for other classes will vary. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

02.28 Select Portfolios: Fidelity Advisor Materials Fund - AMCIZ PRO-12 | Materials Portfolio | Fidelity Advisor Materials Fund: Class A

Risk/Return:

rr_RiskReturnAbstract

Maximum sales charge (load) on purchases (as a % of offering price)

rr_MaximumCumulativeSalesChargeOverOfferingPrice

5.75%

Maximum contingent deferred sales charge (as a % of the lesser of original purchase price or redemption proceeds)

rr_MaximumDeferredSalesChargeOverOther

none

^[1]

Management fee

rr_ManagementFeesOverAssets

0.53%

Distribution and/or Service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

0.25%

Other expenses

rr_OtherExpensesOverAssets

0.30%

Total annual operating expenses

rr_ExpensesOverAssets

1.08%

Expenses Deferred Charges [Text Block]

rr_ExpensesDeferredChargesTextBlock

Class A and Class M purchases of $1 million or more will not be subject to a front-end sales charge. Such Class A and Class M purchases may be subject, upon redemption, to a contingent deferred sales charge (CDSC) of 1.00% or 0.25%, respectively.

1 year

rr_ExpenseExampleYear01

$ 679

3 years

rr_ExpenseExampleYear03

899

5 years

rr_ExpenseExampleYear05

1,136

10 years

rr_ExpenseExampleYear10

1,816

1 Year

rr_ExpenseExampleNoRedemptionYear01

679

3 Years

rr_ExpenseExampleNoRedemptionYear03

899

5 Years

rr_ExpenseExampleNoRedemptionYear05

1,136

10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 1,816

2010

rr_AnnualReturn2010

27.73%

2011

rr_AnnualReturn2011

(8.46%)

2012

rr_AnnualReturn2012

19.83%

2013

rr_AnnualReturn2013

21.56%

2014

rr_AnnualReturn2014

(0.32%)

2015

rr_AnnualReturn2015

(8.91%)

2016

rr_AnnualReturn2016

11.71%

2017

rr_AnnualReturn2017

25.86%

2018

rr_AnnualReturn2018

(23.85%)

2019

rr_AnnualReturn2019

12.10%

Year to Date Return, Label

rr_YearToDateReturnLabel

Year-to-Date Return

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Mar. 31, 2020

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

(26.36%)

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Highest Quarter Return

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Dec. 31, 2010

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

20.81%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Lowest Quarter Return

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Sep. 30, 2011

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(25.35%)

02.28 Select Portfolios: Fidelity Advisor Materials Fund - AMCIZ PRO-12 | Materials Portfolio | Fidelity Advisor Materials Fund: Class M

Risk/Return:

rr_RiskReturnAbstract

Maximum sales charge (load) on purchases (as a % of offering price)

rr_MaximumCumulativeSalesChargeOverOfferingPrice

3.50%

Maximum contingent deferred sales charge (as a % of the lesser of original purchase price or redemption proceeds)

rr_MaximumDeferredSalesChargeOverOther

none

^[1]

Management fee

rr_ManagementFeesOverAssets

0.53%

Distribution and/or Service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

0.50%

Other expenses

rr_OtherExpensesOverAssets

0.34%

Total annual operating expenses

rr_ExpensesOverAssets

1.37%

Expenses Deferred Charges [Text Block]

rr_ExpensesDeferredChargesTextBlock

Class A and Class M purchases of $1 million or more will not be subject to a front-end sales charge. Such Class A and Class M purchases may be subject, upon redemption, to a contingent deferred sales charge (CDSC) of 1.00% or 0.25%, respectively.

1 year

rr_ExpenseExampleYear01

$ 485

3 years

rr_ExpenseExampleYear03

769

5 years

rr_ExpenseExampleYear05

1,074

10 years

rr_ExpenseExampleYear10

1,939

1 Year

rr_ExpenseExampleNoRedemptionYear01

485

3 Years

rr_ExpenseExampleNoRedemptionYear03

769

5 Years

rr_ExpenseExampleNoRedemptionYear05

1,074

10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 1,939

02.28 Select Portfolios: Fidelity Advisor Materials Fund - AMCIZ PRO-12 | Materials Portfolio | Fidelity Advisor Materials Fund: Class C

Risk/Return:

rr_RiskReturnAbstract

Maximum sales charge (load) on purchases (as a % of offering price)

rr_MaximumCumulativeSalesChargeOverOfferingPrice

none

Maximum contingent deferred sales charge (as a % of the lesser of original purchase price or redemption proceeds)

rr_MaximumDeferredSalesChargeOverOther

1.00%

^[2]

Management fee

rr_ManagementFeesOverAssets

0.53%

Distribution and/or Service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

1.00%

Other expenses

rr_OtherExpensesOverAssets

0.29%

Total annual operating expenses

rr_ExpensesOverAssets

1.82%

Expenses Deferred Charges [Text Block]

rr_ExpensesDeferredChargesTextBlock

On Class C shares redeemed less than one year after purchase.

1 year

rr_ExpenseExampleYear01

$ 285

3 years

rr_ExpenseExampleYear03

573

5 years

rr_ExpenseExampleYear05

985

10 years

rr_ExpenseExampleYear10

2,137

1 Year

rr_ExpenseExampleNoRedemptionYear01

185

3 Years

rr_ExpenseExampleNoRedemptionYear03

573

5 Years

rr_ExpenseExampleNoRedemptionYear05

985

10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 2,137

02.28 Select Portfolios: Fidelity Advisor Materials Fund - AMCIZ PRO-12 | Materials Portfolio | Fidelity Advisor Materials Fund: Class I

Risk/Return:

rr_RiskReturnAbstract

Maximum sales charge (load) on purchases (as a % of offering price)

rr_MaximumCumulativeSalesChargeOverOfferingPrice

none

Maximum contingent deferred sales charge (as a % of the lesser of original purchase price or redemption proceeds)

rr_MaximumDeferredSalesChargeOverOther

none

Management fee

rr_ManagementFeesOverAssets

0.53%

Distribution and/or Service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

none

Other expenses

rr_OtherExpensesOverAssets

0.26%

Total annual operating expenses

rr_ExpensesOverAssets

0.79%

1 year

rr_ExpenseExampleYear01

$ 81

3 years

rr_ExpenseExampleYear03

252

5 years

rr_ExpenseExampleYear05

439

10 years

rr_ExpenseExampleYear10

978

1 Year

rr_ExpenseExampleNoRedemptionYear01

81

3 Years

rr_ExpenseExampleNoRedemptionYear03

252

5 Years

rr_ExpenseExampleNoRedemptionYear05

439

10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 978

02.28 Select Portfolios: Fidelity Advisor Materials Fund - AMCIZ PRO-12 | Materials Portfolio | Fidelity Advisor Materials Fund: Class Z

Risk/Return:

rr_RiskReturnAbstract

Maximum sales charge (load) on purchases (as a % of offering price)

rr_MaximumCumulativeSalesChargeOverOfferingPrice

none

Maximum contingent deferred sales charge (as a % of the lesser of original purchase price or redemption proceeds)

rr_MaximumDeferredSalesChargeOverOther

none

Management fee

rr_ManagementFeesOverAssets

0.53%

Distribution and/or Service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

none

Other expenses

rr_OtherExpensesOverAssets

0.10%

Total annual operating expenses

rr_ExpensesOverAssets

0.63%

1 year

rr_ExpenseExampleYear01

$ 64

3 years

rr_ExpenseExampleYear03

202

5 years

rr_ExpenseExampleYear05

351

10 years

rr_ExpenseExampleYear10

786

1 Year

rr_ExpenseExampleNoRedemptionYear01

64

3 Years

rr_ExpenseExampleNoRedemptionYear03

202

5 Years

rr_ExpenseExampleNoRedemptionYear05

351

10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 786

02.28 Select Portfolios: Fidelity Advisor Materials Fund - AMCIZ PRO-12 | Materials Portfolio | Return Before Taxes | Fidelity Advisor Materials Fund: Class A

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Materials Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Class A - Return Before Taxes</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

5.65%

Past 5 years

rr_AverageAnnualReturnYear05

0.60%

Past 10 years

rr_AverageAnnualReturnYear10

5.75%

02.28 Select Portfolios: Fidelity Advisor Materials Fund - AMCIZ PRO-12 | Materials Portfolio | Return Before Taxes | Fidelity Advisor Materials Fund: Class M

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Materials Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Class M - Return Before Taxes</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

7.85%

Past 5 years

rr_AverageAnnualReturnYear05

0.77%

Past 10 years

rr_AverageAnnualReturnYear10

5.69%

02.28 Select Portfolios: Fidelity Advisor Materials Fund - AMCIZ PRO-12 | Materials Portfolio | Return Before Taxes | Fidelity Advisor Materials Fund: Class C

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Materials Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Class C - Return Before Taxes</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

10.26%

Past 5 years

rr_AverageAnnualReturnYear05

1.04%

Past 10 years

rr_AverageAnnualReturnYear10

5.58%

02.28 Select Portfolios: Fidelity Advisor Materials Fund - AMCIZ PRO-12 | Materials Portfolio | Return Before Taxes | Fidelity Advisor Materials Fund: Class I

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Materials Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Class I - Return Before Taxes</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

12.41%

Past 5 years

rr_AverageAnnualReturnYear05

2.09%

Past 10 years

rr_AverageAnnualReturnYear10

6.68%

02.28 Select Portfolios: Fidelity Advisor Materials Fund - AMCIZ PRO-12 | Materials Portfolio | Return Before Taxes | Fidelity Advisor Materials Fund: Class Z

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Materials Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Class Z - Return Before Taxes</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

12.59%

Past 10 years

rr_AverageAnnualReturnYear10

Since Inception

rr_AverageAnnualReturnSinceInception

(5.69%)

^[3]

Inception Date

rr_AverageAnnualReturnInceptionDate

Oct. 02, 2018

02.28 Select Portfolios: Fidelity Advisor Materials Fund - AMCIZ PRO-12 | Materials Portfolio | After Taxes on Distributions | Fidelity Advisor Materials Fund: Class A

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Materials Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

5.41%

Past 5 years

rr_AverageAnnualReturnYear05

(0.33%)

Past 10 years

rr_AverageAnnualReturnYear10

4.88%

02.28 Select Portfolios: Fidelity Advisor Materials Fund - AMCIZ PRO-12 | Materials Portfolio | After Taxes on Distributions and Sales | Fidelity Advisor Materials Fund: Class A

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Materials Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions and Sale of Fund Shares</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

3.52%

Past 5 years

rr_AverageAnnualReturnYear05

0.46%

Past 10 years

rr_AverageAnnualReturnYear10

4.62%

02.28 Select Portfolios: Fidelity Advisor Materials Fund - AMCIZ PRO-12 | Materials Portfolio | S&P 500® Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

31.49%

Past 5 years

rr_AverageAnnualReturnYear05

11.70%

Past 10 years

rr_AverageAnnualReturnYear10

13.56%

02.28 Select Portfolios: Fidelity Advisor Materials Fund - AMCIZ PRO-12 | Materials Portfolio | MSCI U.S. IMI Materials 25-50 Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

23.80%

Past 5 years

rr_AverageAnnualReturnYear05

6.70%

Past 10 years

rr_AverageAnnualReturnYear10

9.30%

[1] Class A and Class M purchases of $1 million or more will not be subject to a front-end sales charge. Such Class A and Class M purchases may be subject, upon redemption, to a contingent deferred sales charge (CDSC) of 1.00% or 0.25%, respectively.

[2] On Class C shares redeemed less than one year after purchase.

[3] Since inception October 2, 2018.

XML

Total

02.28 Select Portfolios: Group 5 Health Care Sector Combo PRO-13 | Health Care Services Portfolio

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: bold 12pt Arial, Helvetica, sans-serif;">Fund:<br/>Health Care Services Portfolio</p>

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

The fund seeks capital appreciation.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

Shareholder Fees {- Health Care Services Portfolio}	02.28 Select Portfolios: Group 5 Health Care Sector Combo PRO-13 Health Care Services Portfolio USD ($)
(fees paid directly from your investment)	none

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Annual Operating Expenses {- Health Care Services Portfolio}	02.28 Select Portfolios: Group 5 Health Care Sector Combo PRO-13 Health Care Services Portfolio Health Care Services Portfolio-Default
Management fee	0.54%
Distribution and/or Service (12b-1) fees	none
Other expenses	0.21%
Total annual operating expenses	0.75%

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Expense Example {- Health Care Services Portfolio}	02.28 Select Portfolios: Group 5 Health Care Sector Combo PRO-13 Health Care Services Portfolio Health Care Services Portfolio-Default USD ($)
1 year	$ 77
3 years	240
5 years	417
10 years	$ 930

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 37% of the average value of its portfolio.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in the ownership or management of hospitals, nursing homes, health maintenance organizations, and other companies specializing in the delivery of health care services.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Health Care Services Industry Concentration. The health care services industry is subject to extensive government regulation and can be significantly affected by government reimbursement for medical expenses, rising costs of medical products and services, pricing pressure, and an increased emphasis on outpatient services.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	26.24%	December 31, 2019
Lowest Quarter Return	-17.91%	September 30, 2011
Year-to-Date Return	-13.30%	March 31, 2020

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

Average Annual Total Returns{- Health Care Services Portfolio} - 02.28 Select Portfolios: Group 5 Health Care Sector Combo PRO-13 - Health Care Services Portfolio	Past 1 year	Past 5 years	Past 10 years
Health Care Services Portfolio-Default | Return Before Taxes	19.91%	12.48%	15.54%
Health Care Services Portfolio-Default | After Taxes on Distributions	19.83%	10.69%	14.02%
Health Care Services Portfolio-Default | After Taxes on Distributions and Sales	11.84%	9.59%	12.70%
S&P 500® Index(reflects no deduction for fees, expenses, or taxes)	31.49%	11.70%	13.56%
MSCI U.S. IMI Health Care Providers & Services 25-50 Index(reflects no deduction for fees, expenses, or taxes)	19.38%	11.92%	16.54%

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Total

02.28 Select Portfolios: Group 1 Consumer Discretionary Sector Combo PRO-16 | Communication Services Portfolio

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: normal 12pt Arial, Helvetica, sans-serif;"><b>Fund/Class</b>:<br/><b>Communication Services Portfolio</b>/Communication Services Portfolio</p>

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

The fund seeks capital appreciation.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

Shareholder Fees {- Communication Services Portfolio}	02.28 Select Portfolios: Group 1 Consumer Discretionary Sector Combo PRO-16 Communication Services Portfolio USD ($)
(fees paid directly from your investment)	none

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Annual Operating Expenses {- Communication Services Portfolio}	02.28 Select Portfolios: Group 1 Consumer Discretionary Sector Combo PRO-16 Communication Services Portfolio Communication Services Portfolio
Management fee	0.54%
Distribution and/or Service (12b-1) fees	none
Other expenses	0.24%
Total annual operating expenses	0.78%

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Expense Example {- Communication Services Portfolio}	02.28 Select Portfolios: Group 1 Consumer Discretionary Sector Combo PRO-16 Communication Services Portfolio Communication Services Portfolio USD ($)
1 year	$ 80
3 years	249
5 years	433
10 years	$ 966

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 73% of the average value of its portfolio.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in the development, production, or distribution of communication services.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Communication Services Concentration. The communication services industries can be significantly affected by government regulation, intense competition, technology changes, general economic conditions, consumer and business confidence and spending, and changes in consumer and business preferences.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Prior to December 1, 2018, the fund was named Multimedia Portfolio, and the fund operated under certain different investment policies and compared its performance to a different additional index. The fund's historical performance may not represent its current investment policies. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	16.03%	March 31, 2012
Lowest Quarter Return	-20.43%	September 30, 2011
Year-to-Date Return	-16.73%	March 31, 2020

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

Average Annual Total Returns{- Communication Services Portfolio} - 02.28 Select Portfolios: Group 1 Consumer Discretionary Sector Combo PRO-16 - Communication Services Portfolio	Past 1 year	Past 5 years	Past 10 years
Communication Services Portfolio | Return Before Taxes	32.62%	9.12%	15.42%
Communication Services Portfolio | After Taxes on Distributions	23.35%	5.87%	13.32%
Communication Services Portfolio | After Taxes on Distributions and Sales	24.71%	6.72%	12.69%
S&P 500® Index(reflects no deduction for fees, expenses, or taxes)	31.49%	11.70%	13.56%
MSCI U.S. IMI Communication Services 25-50 (Media Linked) Index(reflects no deduction for fees, expenses, or taxes)	27.94%	7.41%	16.02%

XML

Total

02.28 Select Portfolios: Group 6 Industrials Sector Combo PRO-10 | Environment and Alternative Energy Portfolio

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: bold 12pt Arial, Helvetica, sans-serif;">Fund:<br/>Environment and Alternative Energy Portfolio</p>

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

The fund seeks capital appreciation.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

Shareholder Fees {- Environment and Alternative Energy Portfolio}	02.28 Select Portfolios: Group 6 Industrials Sector Combo PRO-10 Environment and Alternative Energy Portfolio USD ($)
(fees paid directly from your investment)	none

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Annual Operating Expenses {- Environment and Alternative Energy Portfolio}	02.28 Select Portfolios: Group 6 Industrials Sector Combo PRO-10 Environment and Alternative Energy Portfolio Environment and Alternative Energy Portfolio-Default
Management fee	0.54%
Distribution and/or Service (12b-1) fees	none
Other expenses	0.31%
Total annual operating expenses	0.85%

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Expense Example {- Environment and Alternative Energy Portfolio}	02.28 Select Portfolios: Group 6 Industrials Sector Combo PRO-10 Environment and Alternative Energy Portfolio Environment and Alternative Energy Portfolio-Default USD ($)
1 year	$ 87
3 years	271
5 years	471
10 years	$ 1,049

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 49% of the average value of its portfolio.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in business activities related to alternative and renewable energy, energy efficiency, pollution control, water infrastructure, waste and recycling technologies, or other environmental support services.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Environment and Alternative Energy Industry Concentration. The environment and alternative energy industries can be significantly affected by government regulations and subsidies, changing supply and demand for traditional energy sources, and availability of funding for remedial cleanup or development of new technologies, and can be subject to risks associated with hazardous materials.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Prior to July 1, 2010, the fund was named Environmental Portfolio, and the fund operated under certain different investment policies and compared its performance to a different additional index. The fund's historical performance may not represent its current investment policies. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	15.66%	March 31, 2019
Lowest Quarter Return	-25.92%	September 30, 2011
Year-to-Date Return	-26.22%	March 31, 2020

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

Average Annual Total Returns{- Environment and Alternative Energy Portfolio} - 02.28 Select Portfolios: Group 6 Industrials Sector Combo PRO-10 - Environment and Alternative Energy Portfolio	Past 1 year	Past 5 years	Past 10 years
Environment and Alternative Energy Portfolio-Default | Return Before Taxes	26.83%	9.64%	9.37%
Environment and Alternative Energy Portfolio-Default | After Taxes on Distributions	26.17%	8.62%	8.48%
Environment and Alternative Energy Portfolio-Default | After Taxes on Distributions and Sales	16.33%	7.44%	7.50%
S&P 500® Index(reflects no deduction for fees, expenses, or taxes)	31.49%	11.70%	13.56%
FTSE® Environmental Opportunities & Alternative Energy Index(reflects no deduction for fees, expenses, or taxes)	33.55%	11.50%	11.88%

XML

Label

Element

Value

Risk/Return:

rr_RiskReturnAbstract

Registrant Name

dei_EntityRegistrantName

FIDELITY SELECT PORTFOLIOS

Prospectus Date

rr_ProspectusDate

Apr. 29, 2020

02.28 Select Portfolios: Group 7 Information Technology Sector Combo PRO-16 | Communications Equipment Portfolio

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: bold 12pt Arial, Helvetica, sans-serif;">Fund:<br/>Communications Equipment Portfolio</p>

Objective [Heading]

rr_ObjectiveHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks capital appreciation.

Expense [Heading]

rr_ExpenseHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

Shareholder Fees Caption [Text]

rr_ShareholderFeesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

(fees paid directly from your investment)

rr_ShareholderFeeOther

none

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

Portfolio Turnover [Text Block]

rr_PortfolioTurnoverTextBlock

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 108% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

108.00%

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Strategy [Heading]

rr_StrategyHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in the development, manufacture, or sale of communications equipment.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

Strategy Portfolio Concentration [Text]

rr_StrategyPortfolioConcentration

<font style="FONT-FAMILY: Times New Roman" size="3">Normally investing at least 80% of assets in securities of companies principally engaged in the development, manufacture, or sale of communications equipment.</font>

Risk [Heading]

rr_RiskHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Communications Equipment Industry Concentration. The communications equipment industry can be significantly affected by failure to obtain, or delays in obtaining, financing or regulatory approval, intense competition, product compatibility, consumer preferences, corporate capital expenditures, and rapid obsolescence.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

• High Portfolio Turnover. High portfolio turnover (more than 100%) may result in increased transaction costs and potentially higher capital gains or losses. The effects of higher than normal portfolio turnover may adversely affect the fund's performance.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

Risk Lose Money [Text]

rr_RiskLoseMoney

<font style="FONT-FAMILY: Times New Roman" size="3">You could lose money by investing in the fund.</font>

Risk Nondiversified Status [Text]

rr_RiskNondiversifiedStatus

<font style="FONT-FAMILY: Times New Roman" size="3">In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.</font>

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

<font style="FONT-FAMILY: Times New Roman" size="3">An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</font>

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

<font style="FONT-FAMILY: Times New Roman" size="3">The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time.</font>

Performance Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

<font style="FONT-FAMILY: Times New Roman" size="3">www.fidelity.com </font>

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

<font style="FONT-FAMILY: Times New Roman" size="3">Past performance (before and after taxes) is not an indication of future performance.</font>

Bar Chart [Heading]

rr_BarChartHeading

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	20.01%	September 30, 2010
Lowest Quarter Return	-25.14%	September 30, 2011
Year-to-Date Return	-19.79%	March 31, 2020

Performance Table Heading

rr_PerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

<font style="FONT-FAMILY: Times New Roman" size="3">After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes.</font>

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

<font style="FONT-FAMILY: Times New Roman" size="3">The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan).</font>

Performance Table Explanation after Tax Higher

rr_PerformanceTableExplanationAfterTaxHigher

<font style="FONT-FAMILY: Times New Roman" size="3">Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.</font>

Performance Table Narrative

rr_PerformanceTableNarrativeTextBlock

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

02.28 Select Portfolios: Group 7 Information Technology Sector Combo PRO-16 | Communications Equipment Portfolio | Communications Equipment Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Management fee

rr_ManagementFeesOverAssets

0.53%

Distribution and/or Service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

none

Other expenses

rr_OtherExpensesOverAssets

0.30%

Total annual operating expenses

rr_ExpensesOverAssets

0.83%

1 year

rr_ExpenseExampleYear01

$ 85

3 years

rr_ExpenseExampleYear03

265

5 years

rr_ExpenseExampleYear05

460

10 years

rr_ExpenseExampleYear10

$ 1,025

2010

rr_AnnualReturn2010

27.70%

2011

rr_AnnualReturn2011

(16.68%)

2012

rr_AnnualReturn2012

5.97%

2013

rr_AnnualReturn2013

28.16%

2014

rr_AnnualReturn2014

14.97%

2015

rr_AnnualReturn2015

(10.18%)

2016

rr_AnnualReturn2016

19.88%

2017

rr_AnnualReturn2017

11.66%

2018

rr_AnnualReturn2018

3.95%

2019

rr_AnnualReturn2019

6.09%

Year to Date Return, Label

rr_YearToDateReturnLabel

Year-to-Date Return

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Mar. 31, 2020

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

(19.79%)

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Highest Quarter Return

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Sep. 30, 2010

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

20.01%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Lowest Quarter Return

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Sep. 30, 2011

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(25.14%)

02.28 Select Portfolios: Group 7 Information Technology Sector Combo PRO-16 | Communications Equipment Portfolio | Return Before Taxes | Communications Equipment Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Communications Equipment Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return Before Taxes</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

6.09%

Past 5 years

rr_AverageAnnualReturnYear05

5.81%

Past 10 years

rr_AverageAnnualReturnYear10

8.22%

02.28 Select Portfolios: Group 7 Information Technology Sector Combo PRO-16 | Communications Equipment Portfolio | After Taxes on Distributions | Communications Equipment Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Communications Equipment Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

4.85%

Past 5 years

rr_AverageAnnualReturnYear05

4.82%

Past 10 years

rr_AverageAnnualReturnYear10

7.47%

02.28 Select Portfolios: Group 7 Information Technology Sector Combo PRO-16 | Communications Equipment Portfolio | After Taxes on Distributions and Sales | Communications Equipment Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Communications Equipment Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions and Sale of Fund Shares</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

4.57%

Past 5 years

rr_AverageAnnualReturnYear05

4.42%

Past 10 years

rr_AverageAnnualReturnYear10

6.55%

02.28 Select Portfolios: Group 7 Information Technology Sector Combo PRO-16 | Communications Equipment Portfolio | S&P 500® Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

31.49%

Past 5 years

rr_AverageAnnualReturnYear05

11.70%

Past 10 years

rr_AverageAnnualReturnYear10

13.56%

02.28 Select Portfolios: Group 7 Information Technology Sector Combo PRO-16 | Communications Equipment Portfolio | MSCI North America IMI + ADR Custom Communications Equipment 25/50 Linked Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

6.09%

Past 5 years

rr_AverageAnnualReturnYear05

5.32%

Past 10 years

rr_AverageAnnualReturnYear10

6.46%

XML

Label

Element

Value

Risk/Return:

rr_RiskReturnAbstract

Registrant Name

dei_EntityRegistrantName

FIDELITY SELECT PORTFOLIOS

Prospectus Date

rr_ProspectusDate

Apr. 29, 2020

02.28 Select Portfolios: Fidelity Advisor Consumer Staples Fund - AMCIZ PRO-13 | Consumer Staples Portfolio

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: normal 12pt Arial, Helvetica, sans-serif;"><b>Fund/Class</b>:<br/><b>Consumer Staples Portfolio</b>/Fidelity Advisor® Consumer Staples Fund A, M, C, I, Z</p>

Objective [Heading]

rr_ObjectiveHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks capital appreciation.

Expense [Heading]

rr_ExpenseHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund. In addition to the fees and expenses described below, your broker may also require you to pay brokerage commissions on purchases and sales of certain share classes of the fund.

You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $50,000 in the fund or certain other Fidelity^® funds. More information about these and other discounts is available from your investment professional and in the "Fund Distribution" section beginning on page 27 of the prospectus. Different intermediaries may provide additional waivers or reductions of the sales charge. Please see “Sales Charge Waiver Policies Applied by Certain Intermediaries” in the “Appendix” section of the prospectus.

Shareholder Fees Caption [Text]

rr_ShareholderFeesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(fees paid directly from your investment)</p>

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

Portfolio Turnover [Text Block]

rr_PortfolioTurnoverTextBlock

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 40% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

40.00%

Expense Breakpoint Discounts [Text]

rr_ExpenseBreakpointDiscounts

<font style="FONT-FAMILY: Times New Roman" size="3">You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $50,000 in the fund or certain other Fidelity® funds. More information about these and other discounts is available from your investment professional and in the "Fund Distribution" section beginning on page 27 of the prospectus.</font>

Expense Breakpoint, Minimum Investment Required [Amount]

rr_ExpenseBreakpointMinimumInvestmentRequiredAmount

$ 50,000

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated and if you hold your shares:

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Expense Example, No Redemption, By Year, Caption [Text]

rr_ExpenseExampleNoRedemptionByYearCaption

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Hold Shares</p>

Strategy [Heading]

rr_StrategyHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in the manufacture, sale, or distribution of consumer staples.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

Strategy Portfolio Concentration [Text]

rr_StrategyPortfolioConcentration

<font style="FONT-FAMILY: Times New Roman" size="3">Normally investing at least 80% of assets in securities of companies principally engaged in the manufacture, sale, or distribution of consumer staples.</font>

Risk [Heading]

rr_RiskHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Consumer Staples Industry Concentration. The consumer staples industries can be significantly affected by demographics and product trends, competitive pricing, food fads, marketing campaigns, environmental factors, government regulation, the performance of the overall economy, interest rates, consumer confidence, and the cost of commodities.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

Risk Lose Money [Text]

rr_RiskLoseMoney

<font style="FONT-FAMILY: Times New Roman" size="3">You could lose money by investing in the fund.</font>

Risk Nondiversified Status [Text]

rr_RiskNondiversifiedStatus

<font style="FONT-FAMILY: Times New Roman" size="3">In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.</font>

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

<font style="FONT-FAMILY: Times New Roman" size="3">An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</font>

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit institutional.fidelity.com for more recent performance information.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

<font style="FONT-FAMILY: Times New Roman" size="3">The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time.</font>

Performance Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

<font style="FONT-FAMILY: Times New Roman" size="3">institutional.fidelity.com</font>

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

<font style="FONT-FAMILY: Times New Roman" size="3">Past performance (before and after taxes) is not an indication of future performance.</font>

Bar Chart [Heading]

rr_BarChartHeading

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

Bar Chart Narrative [Text Block]

rr_BarChartNarrativeTextBlock

The returns in the bar chart do not reflect any applicable sales charges; if sales charges were reflected, returns would be lower than those shown.

Bar Chart Does Not Reflect Sales Loads [Text]

rr_BarChartDoesNotReflectSalesLoads

<font style="FONT-FAMILY: Times New Roman" size="3">The returns in the bar chart do not reflect any applicable sales charges; if sales charges were reflected, returns would be lower than those shown.</font>

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

During the periods shown in the chart for Class A:	Returns	Quarter ended
Highest Quarter Return	17.13%	March 31, 2019
Lowest Quarter Return	-10.60%	December 31, 2018
Year-to-Date Return	-16.65%	March 31, 2020

Performance Table Heading

rr_PerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

Performance Table Does Reflect Sales Loads

rr_PerformanceTableDoesReflectSalesLoads

<font style="FONT-FAMILY: Times New Roman" size="3">Unlike the returns in the bar chart, the returns in the table reflect the maximum applicable sales charges.</font>

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

<font style="FONT-FAMILY: Times New Roman" size="3">After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes.</font>

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

<font style="FONT-FAMILY: Times New Roman" size="3">The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan).</font>

Performance Table One Class of after Tax Shown [Text]

rr_PerformanceTableOneClassOfAfterTaxShown

<font style="FONT-FAMILY: Times New Roman" size="3">After-tax returns for Class A are shown in the table below and after-tax returns for other classes will vary.</font>

Performance Table Explanation after Tax Higher

rr_PerformanceTableExplanationAfterTaxHigher

<font style="FONT-FAMILY: Times New Roman" size="3">Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.</font>

Performance Table Narrative

rr_PerformanceTableNarrativeTextBlock

Unlike the returns in the bar chart, the returns in the table reflect the maximum applicable sales charges. After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. After-tax returns for Class A are shown in the table below and after-tax returns for other classes will vary. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

02.28 Select Portfolios: Fidelity Advisor Consumer Staples Fund - AMCIZ PRO-13 | Consumer Staples Portfolio | Fidelity Advisor Consumer Staples Fund: Class A

Risk/Return:

rr_RiskReturnAbstract

Maximum sales charge (load) on purchases (as a % of offering price)

rr_MaximumCumulativeSalesChargeOverOfferingPrice

5.75%

Maximum contingent deferred sales charge (as a % of the lesser of original purchase price or redemption proceeds)

rr_MaximumDeferredSalesChargeOverOther

none

^[1]

Management fee

rr_ManagementFeesOverAssets

0.54%

Distribution and/or Service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

0.25%

Other expenses

rr_OtherExpensesOverAssets

0.25%

Total annual operating expenses

rr_ExpensesOverAssets

1.04%

Expenses Deferred Charges [Text Block]

rr_ExpensesDeferredChargesTextBlock

Class A and Class M purchases of $1 million or more will not be subject to a front-end sales charge. Such Class A and Class M purchases may be subject, upon redemption, to a contingent deferred sales charge (CDSC) of 1.00% or 0.25%, respectively.

1 year

rr_ExpenseExampleYear01

$ 675

3 years

rr_ExpenseExampleYear03

887

5 years

rr_ExpenseExampleYear05

1,116

10 years

rr_ExpenseExampleYear10

1,773

1 Year

rr_ExpenseExampleNoRedemptionYear01

675

3 Years

rr_ExpenseExampleNoRedemptionYear03

887

5 Years

rr_ExpenseExampleNoRedemptionYear05

1,116

10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 1,773

2010

rr_AnnualReturn2010

14.92%

2011

rr_AnnualReturn2011

8.56%

2012

rr_AnnualReturn2012

15.06%

2013

rr_AnnualReturn2013

21.31%

2014

rr_AnnualReturn2014

14.59%

2015

rr_AnnualReturn2015

1.63%

2016

rr_AnnualReturn2016

2.78%

2017

rr_AnnualReturn2017

11.75%

2018

rr_AnnualReturn2018

(16.07%)

2019

rr_AnnualReturn2019

31.38%

Year to Date Return, Label

rr_YearToDateReturnLabel

Year-to-Date Return

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Mar. 31, 2020

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

(16.65%)

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Highest Quarter Return

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Mar. 31, 2019

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

17.13%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Lowest Quarter Return

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Dec. 31, 2018

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(10.60%)

02.28 Select Portfolios: Fidelity Advisor Consumer Staples Fund - AMCIZ PRO-13 | Consumer Staples Portfolio | Fidelity Advisor Consumer Staples Fund: Class M

Risk/Return:

rr_RiskReturnAbstract

Maximum sales charge (load) on purchases (as a % of offering price)

rr_MaximumCumulativeSalesChargeOverOfferingPrice

3.50%

Maximum contingent deferred sales charge (as a % of the lesser of original purchase price or redemption proceeds)

rr_MaximumDeferredSalesChargeOverOther

none

^[1]

Management fee

rr_ManagementFeesOverAssets

0.54%

Distribution and/or Service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

0.50%

Other expenses

rr_OtherExpensesOverAssets

0.27%

Total annual operating expenses

rr_ExpensesOverAssets

1.31%

Expenses Deferred Charges [Text Block]

rr_ExpensesDeferredChargesTextBlock

Class A and Class M purchases of $1 million or more will not be subject to a front-end sales charge. Such Class A and Class M purchases may be subject, upon redemption, to a contingent deferred sales charge (CDSC) of 1.00% or 0.25%, respectively.

1 year

rr_ExpenseExampleYear01

$ 479

3 years

rr_ExpenseExampleYear03

751

5 years

rr_ExpenseExampleYear05

1,043

10 years

rr_ExpenseExampleYear10

1,874

1 Year

rr_ExpenseExampleNoRedemptionYear01

479

3 Years

rr_ExpenseExampleNoRedemptionYear03

751

5 Years

rr_ExpenseExampleNoRedemptionYear05

1,043

10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 1,874

02.28 Select Portfolios: Fidelity Advisor Consumer Staples Fund - AMCIZ PRO-13 | Consumer Staples Portfolio | Fidelity Advisor Consumer Staples Fund: Class C

Risk/Return:

rr_RiskReturnAbstract

Maximum sales charge (load) on purchases (as a % of offering price)

rr_MaximumCumulativeSalesChargeOverOfferingPrice

none

Maximum contingent deferred sales charge (as a % of the lesser of original purchase price or redemption proceeds)

rr_MaximumDeferredSalesChargeOverOther

1.00%

^[2]

Management fee

rr_ManagementFeesOverAssets

0.54%

Distribution and/or Service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

1.00%

Other expenses

rr_OtherExpensesOverAssets

0.25%

Total annual operating expenses

rr_ExpensesOverAssets

1.79%

Expenses Deferred Charges [Text Block]

rr_ExpensesDeferredChargesTextBlock

On Class C shares redeemed less than one year after purchase.

1 year

rr_ExpenseExampleYear01

$ 282

3 years

rr_ExpenseExampleYear03

563

5 years

rr_ExpenseExampleYear05

970

10 years

rr_ExpenseExampleYear10

2,105

1 Year

rr_ExpenseExampleNoRedemptionYear01

182

3 Years

rr_ExpenseExampleNoRedemptionYear03

563

5 Years

rr_ExpenseExampleNoRedemptionYear05

970

10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 2,105

02.28 Select Portfolios: Fidelity Advisor Consumer Staples Fund - AMCIZ PRO-13 | Consumer Staples Portfolio | Fidelity Advisor Consumer Staples Fund: Class I

Risk/Return:

rr_RiskReturnAbstract

Maximum sales charge (load) on purchases (as a % of offering price)

rr_MaximumCumulativeSalesChargeOverOfferingPrice

none

Maximum contingent deferred sales charge (as a % of the lesser of original purchase price or redemption proceeds)

rr_MaximumDeferredSalesChargeOverOther

none

Management fee

rr_ManagementFeesOverAssets

0.54%

Distribution and/or Service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

none

Other expenses

rr_OtherExpensesOverAssets

0.22%

Total annual operating expenses

rr_ExpensesOverAssets

0.76%

1 year

rr_ExpenseExampleYear01

$ 78

3 years

rr_ExpenseExampleYear03

243

5 years

rr_ExpenseExampleYear05

422

10 years

rr_ExpenseExampleYear10

942

1 Year

rr_ExpenseExampleNoRedemptionYear01

78

3 Years

rr_ExpenseExampleNoRedemptionYear03

243

5 Years

rr_ExpenseExampleNoRedemptionYear05

422

10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 942

02.28 Select Portfolios: Fidelity Advisor Consumer Staples Fund - AMCIZ PRO-13 | Consumer Staples Portfolio | Fidelity Advisor Consumer Staples Fund: Class Z

Risk/Return:

rr_RiskReturnAbstract

Maximum sales charge (load) on purchases (as a % of offering price)

rr_MaximumCumulativeSalesChargeOverOfferingPrice

none

Maximum contingent deferred sales charge (as a % of the lesser of original purchase price or redemption proceeds)

rr_MaximumDeferredSalesChargeOverOther

none

Management fee

rr_ManagementFeesOverAssets

0.54%

Distribution and/or Service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

none

Other expenses

rr_OtherExpensesOverAssets

0.09%

Total annual operating expenses

rr_ExpensesOverAssets

0.63%

1 year

rr_ExpenseExampleYear01

$ 64

3 years

rr_ExpenseExampleYear03

202

5 years

rr_ExpenseExampleYear05

351

10 years

rr_ExpenseExampleYear10

786

1 Year

rr_ExpenseExampleNoRedemptionYear01

64

3 Years

rr_ExpenseExampleNoRedemptionYear03

202

5 Years

rr_ExpenseExampleNoRedemptionYear05

351

10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 786

02.28 Select Portfolios: Fidelity Advisor Consumer Staples Fund - AMCIZ PRO-13 | Consumer Staples Portfolio | Return Before Taxes | Fidelity Advisor Consumer Staples Fund: Class A

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Consumer Staples Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Class A - Return Before Taxes</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

23.83%

Past 5 years

rr_AverageAnnualReturnYear05

3.94%

Past 10 years

rr_AverageAnnualReturnYear10

9.24%

02.28 Select Portfolios: Fidelity Advisor Consumer Staples Fund - AMCIZ PRO-13 | Consumer Staples Portfolio | Return Before Taxes | Fidelity Advisor Consumer Staples Fund: Class M

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Consumer Staples Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Class M - Return Before Taxes</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

26.45%

Past 5 years

rr_AverageAnnualReturnYear05

4.15%

Past 10 years

rr_AverageAnnualReturnYear10

9.20%

02.28 Select Portfolios: Fidelity Advisor Consumer Staples Fund - AMCIZ PRO-13 | Consumer Staples Portfolio | Return Before Taxes | Fidelity Advisor Consumer Staples Fund: Class C

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Consumer Staples Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Class C - Return Before Taxes</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

29.42%

Past 5 years

rr_AverageAnnualReturnYear05

4.40%

Past 10 years

rr_AverageAnnualReturnYear10

9.08%

02.28 Select Portfolios: Fidelity Advisor Consumer Staples Fund - AMCIZ PRO-13 | Consumer Staples Portfolio | Return Before Taxes | Fidelity Advisor Consumer Staples Fund: Class I

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Consumer Staples Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Class I - Return Before Taxes</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

31.75%

Past 5 years

rr_AverageAnnualReturnYear05

5.47%

Past 10 years

rr_AverageAnnualReturnYear10

10.18%

02.28 Select Portfolios: Fidelity Advisor Consumer Staples Fund - AMCIZ PRO-13 | Consumer Staples Portfolio | Return Before Taxes | Fidelity Advisor Consumer Staples Fund: Class Z

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Consumer Staples Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Class Z - Return Before Taxes</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

31.93%

Past 10 years

rr_AverageAnnualReturnYear10

Since Inception

rr_AverageAnnualReturnSinceInception

14.11%

^[3]

Inception Date

rr_AverageAnnualReturnInceptionDate

Oct. 02, 2018

02.28 Select Portfolios: Fidelity Advisor Consumer Staples Fund - AMCIZ PRO-13 | Consumer Staples Portfolio | After Taxes on Distributions | Fidelity Advisor Consumer Staples Fund: Class A

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Consumer Staples Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

23.09%

Past 5 years

rr_AverageAnnualReturnYear05

2.22%

Past 10 years

rr_AverageAnnualReturnYear10

7.86%

02.28 Select Portfolios: Fidelity Advisor Consumer Staples Fund - AMCIZ PRO-13 | Consumer Staples Portfolio | After Taxes on Distributions and Sales | Fidelity Advisor Consumer Staples Fund: Class A

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Consumer Staples Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions and Sale of Fund Shares</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

14.63%

Past 5 years

rr_AverageAnnualReturnYear05

2.85%

Past 10 years

rr_AverageAnnualReturnYear10

7.39%

02.28 Select Portfolios: Fidelity Advisor Consumer Staples Fund - AMCIZ PRO-13 | Consumer Staples Portfolio | S&P 500® Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

31.49%

Past 5 years

rr_AverageAnnualReturnYear05

11.70%

Past 10 years

rr_AverageAnnualReturnYear10

13.56%

02.28 Select Portfolios: Fidelity Advisor Consumer Staples Fund - AMCIZ PRO-13 | Consumer Staples Portfolio | MSCI U.S. IMI Consumer Staples 25-50 Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

26.20%

Past 5 years

rr_AverageAnnualReturnYear05

8.03%

Past 10 years

rr_AverageAnnualReturnYear10

12.25%

[1] Class A and Class M purchases of $1 million or more will not be subject to a front-end sales charge. Such Class A and Class M purchases may be subject, upon redemption, to a contingent deferred sales charge (CDSC) of 1.00% or 0.25%, respectively.

[2] On Class C shares redeemed less than one year after purchase.

[3] Since inception October 2, 2018.

XML

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Risk/Return:	rr_RiskReturnAbstract
Document Type	dei_DocumentType	485BPOS
Document Period End Date	dei_DocumentPeriodEndDate	Feb. 29, 2020
Registrant Name	dei_EntityRegistrantName	FIDELITY SELECT PORTFOLIOS
Central Index Key	dei_EntityCentralIndexKey	0000320351
Investment Company Type	dei_EntityInvCompanyType	N-1A
Amendment Flag	dei_AmendmentFlag	false
Document Creation Date	dei_DocumentCreationDate	Apr. 24, 2020
Document Effective Date	dei_DocumentEffectiveDate	Apr. 29, 2020
Prospectus Date	rr_ProspectusDate	Apr. 29, 2020

XML

Label

Element

Value

Risk/Return:

rr_RiskReturnAbstract

Registrant Name

dei_EntityRegistrantName

FIDELITY SELECT PORTFOLIOS

Prospectus Date

rr_ProspectusDate

Apr. 29, 2020

02.28 Select Portfolios: Group 3 Energy Sector Combo PRO-13 | Energy Portfolio

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: bold 12pt Arial, Helvetica, sans-serif;">Fund:<br/>Energy Portfolio</p>

Objective [Heading]

rr_ObjectiveHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks capital appreciation.

Expense [Heading]

rr_ExpenseHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

Shareholder Fees Caption [Text]

rr_ShareholderFeesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

(fees paid directly from your investment)

rr_ShareholderFeeOther

none

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

Portfolio Turnover [Text Block]

rr_PortfolioTurnoverTextBlock

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 79% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

79.00%

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Strategy [Heading]

rr_StrategyHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in the energy field, including the conventional areas of oil, gas, electricity, and coal, and newer sources of energy such as nuclear, geothermal, oil shale, and solar power.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

Strategy Portfolio Concentration [Text]

rr_StrategyPortfolioConcentration

<font style="FONT-FAMILY: Times New Roman" size="3">Normally investing at least 80% of assets in securities of companies principally engaged in the energy field, including the conventional areas of oil, gas, electricity, and coal, and newer sources of energy such as nuclear, geothermal, oil shale, and solar power.</font>

Risk [Heading]

rr_RiskHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Energy Industry Concentration. The energy industries can be significantly affected by fluctuations in energy prices and supply and demand of energy fuels, energy conservation, the success of exploration projects, and tax and other government regulations.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

Risk Lose Money [Text]

rr_RiskLoseMoney

<font style="FONT-FAMILY: Times New Roman" size="3">You could lose money by investing in the fund.</font>

Risk Nondiversified Status [Text]

rr_RiskNondiversifiedStatus

<font style="FONT-FAMILY: Times New Roman" size="3">In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.</font>

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

<font style="FONT-FAMILY: Times New Roman" size="3">An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</font>

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

<font style="FONT-FAMILY: Times New Roman" size="3">The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time.</font>

Performance Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

<font style="FONT-FAMILY: Times New Roman" size="3">www.fidelity.com </font>

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

<font style="FONT-FAMILY: Times New Roman" size="3">Past performance (before and after taxes) is not an indication of future performance.</font>

Bar Chart [Heading]

rr_BarChartHeading

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	24.43%	December 31, 2010
Lowest Quarter Return	-30.22%	December 31, 2018
Year-to-Date Return	-52.25%	March 31, 2020

Performance Table Heading

rr_PerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

<font style="FONT-FAMILY: Times New Roman" size="3">After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes.</font>

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

<font style="FONT-FAMILY: Times New Roman" size="3">The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan).</font>

Performance Table Explanation after Tax Higher

rr_PerformanceTableExplanationAfterTaxHigher

<font style="FONT-FAMILY: Times New Roman" size="3">Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.</font>

Performance Table Narrative

rr_PerformanceTableNarrativeTextBlock

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

02.28 Select Portfolios: Group 3 Energy Sector Combo PRO-13 | Energy Portfolio | Energy Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Management fee

rr_ManagementFeesOverAssets

0.53%

Distribution and/or Service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

none

Other expenses

rr_OtherExpensesOverAssets

0.28%

Total annual operating expenses

rr_ExpensesOverAssets

0.81%

1 year

rr_ExpenseExampleYear01

$ 83

3 years

rr_ExpenseExampleYear03

259

5 years

rr_ExpenseExampleYear05

450

10 years

rr_ExpenseExampleYear10

$ 1,002

2010

rr_AnnualReturn2010

18.99%

2011

rr_AnnualReturn2011

(4.85%)

2012

rr_AnnualReturn2012

4.64%

2013

rr_AnnualReturn2013

24.21%

2014

rr_AnnualReturn2014

(12.64%)

2015

rr_AnnualReturn2015

(20.53%)

2016

rr_AnnualReturn2016

33.84%

2017

rr_AnnualReturn2017

(2.64%)

2018

rr_AnnualReturn2018

(24.92%)

2019

rr_AnnualReturn2019

9.88%

Year to Date Return, Label

rr_YearToDateReturnLabel

Year-to-Date Return

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Mar. 31, 2020

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

(52.25%)

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Highest Quarter Return

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Dec. 31, 2010

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

24.43%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Lowest Quarter Return

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Dec. 31, 2018

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(30.22%)

02.28 Select Portfolios: Group 3 Energy Sector Combo PRO-13 | Energy Portfolio | Return Before Taxes | Energy Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Energy Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return Before Taxes</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

9.88%

Past 5 years

rr_AverageAnnualReturnYear05

(3.10%)

Past 10 years

rr_AverageAnnualReturnYear10

0.94%

02.28 Select Portfolios: Group 3 Energy Sector Combo PRO-13 | Energy Portfolio | After Taxes on Distributions | Energy Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Energy Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

9.40%

Past 5 years

rr_AverageAnnualReturnYear05

(3.42%)

Past 10 years

rr_AverageAnnualReturnYear10

0.22%

02.28 Select Portfolios: Group 3 Energy Sector Combo PRO-13 | Energy Portfolio | After Taxes on Distributions and Sales | Energy Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Energy Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions and Sale of Fund Shares</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

6.19%

Past 5 years

rr_AverageAnnualReturnYear05

(2.32%)

Past 10 years

rr_AverageAnnualReturnYear10

0.84%

02.28 Select Portfolios: Group 3 Energy Sector Combo PRO-13 | Energy Portfolio | S&P 500® Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

31.49%

Past 5 years

rr_AverageAnnualReturnYear05

11.70%

Past 10 years

rr_AverageAnnualReturnYear10

13.56%

02.28 Select Portfolios: Group 3 Energy Sector Combo PRO-13 | Energy Portfolio | MSCI U.S. IMI Energy 25-50 Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

9.42%

Past 5 years

rr_AverageAnnualReturnYear05

(3.13%)

Past 10 years

rr_AverageAnnualReturnYear10

2.29%

XML

Total

02.28 Select Portfolios: Group 1 Consumer Discretionary Sector Combo PRO-16 | Leisure Portfolio

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: bold 12pt Arial, Helvetica, sans-serif;">Fund:<br/>Leisure Portfolio</p>

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

The fund seeks capital appreciation.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

Shareholder Fees {- Leisure Portfolio}	02.28 Select Portfolios: Group 1 Consumer Discretionary Sector Combo PRO-16 Leisure Portfolio USD ($)
(fees paid directly from your investment)	none

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Annual Operating Expenses {- Leisure Portfolio}	02.28 Select Portfolios: Group 1 Consumer Discretionary Sector Combo PRO-16 Leisure Portfolio Leisure Portfolio-Default
Management fee	0.54%
Distribution and/or Service (12b-1) fees	none
Other expenses	0.22%
Total annual operating expenses	0.76%

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Expense Example {- Leisure Portfolio}	02.28 Select Portfolios: Group 1 Consumer Discretionary Sector Combo PRO-16 Leisure Portfolio Leisure Portfolio-Default USD ($)
1 year	$ 78
3 years	243
5 years	422
10 years	$ 942

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 53% of the average value of its portfolio.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in the design, production, or distribution of goods or services in the leisure industries.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Leisure Industry Concentration. The leisure industry can be significantly affected by the performance of the overall economy, changing consumer tastes, intense competition, and government regulation.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	15.87%	March 31, 2012
Lowest Quarter Return	-14.08%	September 30, 2011
Year-to-Date Return	-32.67%	March 31, 2020

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

Average Annual Total Returns{- Leisure Portfolio} - 02.28 Select Portfolios: Group 1 Consumer Discretionary Sector Combo PRO-16 - Leisure Portfolio	Past 1 year	Past 5 years	Past 10 years
Leisure Portfolio-Default | Return Before Taxes	28.76%	11.13%	15.52%
Leisure Portfolio-Default | After Taxes on Distributions	26.90%	9.28%	13.96%
Leisure Portfolio-Default | After Taxes on Distributions and Sales	18.34%	8.59%	12.79%
S&P 500® Index(reflects no deduction for fees, expenses, or taxes)	31.49%	11.70%	13.56%
MSCI U.S. IMI Consumer Services 25-50 Index(reflects no deduction for fees, expenses, or taxes)	28.29%	13.77%	15.96%

XML

Total

02.28 Select Portfolios: Group 7 Information Technology Sector Combo PRO-16 | Semiconductors Portfolio

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: bold 12pt Arial, Helvetica, sans-serif;">Fund:<br/>Semiconductors Portfolio</p>

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

The fund seeks capital appreciation.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

Shareholder Fees {- Semiconductors Portfolio}	02.28 Select Portfolios: Group 7 Information Technology Sector Combo PRO-16 Semiconductors Portfolio USD ($)
(fees paid directly from your investment)	none

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Annual Operating Expenses {- Semiconductors Portfolio}	02.28 Select Portfolios: Group 7 Information Technology Sector Combo PRO-16 Semiconductors Portfolio Semiconductors Portfolio-Default
Management fee	0.54%
Distribution and/or Service (12b-1) fees	none
Other expenses	0.18%
Total annual operating expenses	0.72%

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Expense Example {- Semiconductors Portfolio}	02.28 Select Portfolios: Group 7 Information Technology Sector Combo PRO-16 Semiconductors Portfolio Semiconductors Portfolio-Default USD ($)
1 year	$ 74
3 years	230
5 years	401
10 years	$ 894

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 114% of the average value of its portfolio.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in the design, manufacture, or sale of semiconductors and semiconductor equipment.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Electronics Industry Concentration. The electronics industry can be significantly affected by rapid obsolescence, intense competition, and global demand.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

• High Portfolio Turnover. High portfolio turnover (more than 100%) may result in increased transaction costs and potentially higher capital gains or losses. The effects of higher than normal portfolio turnover may adversely affect the fund's performance.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	23.64%	March 31, 2012
Lowest Quarter Return	-16.86%	September 30, 2011
Year-to-Date Return	-20.13%	March 31, 2020

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

Average Annual Total Returns{- Semiconductors Portfolio} - 02.28 Select Portfolios: Group 7 Information Technology Sector Combo PRO-16 - Semiconductors Portfolio	Past 1 year	Past 5 years	Past 10 years
Semiconductors Portfolio-Default | Return Before Taxes	64.46%	21.55%	18.92%
Semiconductors Portfolio-Default | After Taxes on Distributions	63.18%	17.45%	16.75%
Semiconductors Portfolio-Default | After Taxes on Distributions and Sales	39.07%	15.72%	15.20%
S&P 500® Index(reflects no deduction for fees, expenses, or taxes)	31.49%	11.70%	13.56%
MSCI U.S. IMI Semiconductors & Semiconductor Equipment 25-50 Index(reflects no deduction for fees, expenses, or taxes)	55.25%	20.18%	17.45%

XML

Total

02.28 Select Portfolios: Group 4 Financials Sector Combo PRO-15 | Brokerage and Investment Management Portfolio

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: bold 12pt Arial, Helvetica, sans-serif;">Fund:<br/>Brokerage and Investment Management Portfolio</p>

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

The fund seeks capital appreciation.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

Shareholder Fees {- Brokerage and Investment Management Portfolio}	02.28 Select Portfolios: Group 4 Financials Sector Combo PRO-15 Brokerage and Investment Management Portfolio USD ($)
(fees paid directly from your investment)	none

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Annual Operating Expenses {- Brokerage and Investment Management Portfolio}	02.28 Select Portfolios: Group 4 Financials Sector Combo PRO-15 Brokerage and Investment Management Portfolio Brokerage and Investment Management Portfolio-Default
Management fee	0.54%
Distribution and/or Service (12b-1) fees	none
Other expenses	0.23%
Total annual operating expenses	0.77%

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Expense Example {- Brokerage and Investment Management Portfolio}	02.28 Select Portfolios: Group 4 Financials Sector Combo PRO-15 Brokerage and Investment Management Portfolio Brokerage and Investment Management Portfolio-Default USD ($)
1 year	$ 79
3 years	246
5 years	428
10 years	$ 954

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 9% of the average value of its portfolio.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in the exchange of financial instruments, stock brokerage, commodity brokerage, investment banking, tax-advantaged investment or investment sales, investment management, or related investment advisory and financial decision support services.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Brokerage and Investment Management Industry Concentration. The brokerage and investment management industry can be significantly affected by stock and bond market activity, changes in regulations, brokerage commission structure, and a competitive environment combined with the high operating leverage inherent in companies in this industry.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	21.95%	March 31, 2012
Lowest Quarter Return	-23.45%	September 30, 2011
Year-to-Date Return	-20.86%	March 31, 2020

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

Average Annual Total Returns{- Brokerage and Investment Management Portfolio} - 02.28 Select Portfolios: Group 4 Financials Sector Combo PRO-15 - Brokerage and Investment Management Portfolio	Past 1 year	Past 5 years	Past 10 years
Brokerage and Investment Management Portfolio-Default | Return Before Taxes	31.60%	6.96%	9.22%
Brokerage and Investment Management Portfolio-Default | After Taxes on Distributions	30.24%	5.54%	8.31%
Brokerage and Investment Management Portfolio-Default | After Taxes on Distributions and Sales	19.58%	5.17%	7.38%
S&P 500® Index(reflects no deduction for fees, expenses, or taxes)	31.49%	11.70%	13.56%
MSCI U.S. IMI Capital Markets 5% Capped Linked Index(reflects no deduction for fees, expenses, or taxes)	31.60%	7.36%	9.83%

XML

Total

02.28 Select Portfolios: Group 9 Telecommunications Services Sector Retail Combo PRO-13 | Wireless Portfolio

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: bold 12pt Arial, Helvetica, sans-serif;">Fund:<br/>Wireless Portfolio</p>

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

The fund seeks capital appreciation.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

Shareholder Fees {- Wireless Portfolio}	02.28 Select Portfolios: Group 9 Telecommunications Services Sector Retail Combo PRO-13 Wireless Portfolio USD ($)
(fees paid directly from your investment)	none

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Annual Operating Expenses {- Wireless Portfolio}	02.28 Select Portfolios: Group 9 Telecommunications Services Sector Retail Combo PRO-13 Wireless Portfolio Wireless Portfolio-Default
Management fee	0.54%
Distribution and/or Service (12b-1) fees	none
Other expenses	0.27%
Total annual operating expenses	0.81%

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Expense Example {- Wireless Portfolio}	02.28 Select Portfolios: Group 9 Telecommunications Services Sector Retail Combo PRO-13 Wireless Portfolio Wireless Portfolio-Default USD ($)
1 year	$ 83
3 years	259
5 years	450
10 years	$ 1,002

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 78% of the average value of its portfolio.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in activities relating to wireless communications services or products.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Wireless Industry Concentration. The wireless industry can be significantly affected by failure or delays in obtaining financing or regulatory approval, intense competition, product incompatibility, changing consumer preferences, rapid obsolescence, significant capital expenditures, and heavy debt burdens.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	15.88%	September 30, 2010
Lowest Quarter Return	-12.62%	December 31, 2018
Year-to-Date Return	-13.02%	March 31, 2020

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

Average Annual Total Returns{- Wireless Portfolio} - 02.28 Select Portfolios: Group 9 Telecommunications Services Sector Retail Combo PRO-13 - Wireless Portfolio	Past 1 year	Past 5 years	Past 10 years
Wireless Portfolio-Default | Return Before Taxes	40.14%	11.88%	11.87%
Wireless Portfolio-Default | After Taxes on Distributions	39.16%	10.01%	10.29%
Wireless Portfolio-Default | After Taxes on Distributions and Sales	24.31%	8.98%	9.39%
S&P 500® Index(reflects no deduction for fees, expenses, or taxes)	31.49%	11.70%	13.56%
Fidelity Wireless Index℠(reflects no deduction for fees, expenses, or taxes)	30.89%	9.08%	8.96%

XML

Total

02.28 Select Portfolios: Group 7 Information Technology Sector Combo PRO-16 | Software and IT Services Portfolio

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: bold 12pt Arial, Helvetica, sans-serif;">Fund:<br/>Software and IT Services Portfolio</p>

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

The fund seeks capital appreciation.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

Shareholder Fees {- Software and IT Services Portfolio}	02.28 Select Portfolios: Group 7 Information Technology Sector Combo PRO-16 Software and IT Services Portfolio USD ($)
(fees paid directly from your investment)	none

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Annual Operating Expenses {- Software and IT Services Portfolio}	02.28 Select Portfolios: Group 7 Information Technology Sector Combo PRO-16 Software and IT Services Portfolio Software and IT Services Portfolio-Default
Management fee	0.54%
Distribution and/or Service (12b-1) fees	none
Other expenses	0.17%	[1]
Total annual operating expenses	0.71%

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Expense Example {- Software and IT Services Portfolio}	02.28 Select Portfolios: Group 7 Information Technology Sector Combo PRO-16 Software and IT Services Portfolio Software and IT Services Portfolio-Default USD ($)
1 year	$ 73
3 years	227
5 years	395
10 years	$ 883

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 23% of the average value of its portfolio.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in research, design, production, or distribution of products or processes that relate to software or information-based services.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Software and Information Technology Services Industry Concentration. The software and information technology services industry can be significantly affected by intense competition, aggressive pricing, technological innovations, and product obsolescence.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	20.44%	March 31, 2012
Lowest Quarter Return	-14.71%	December 31, 2018
Year-to-Date Return	-10.24%	March 31, 2020

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

Average Annual Total Returns{- Software and IT Services Portfolio} - 02.28 Select Portfolios: Group 7 Information Technology Sector Combo PRO-16 - Software and IT Services Portfolio	Past 1 year	Past 5 years	Past 10 years
Software and IT Services Portfolio-Default | Return Before Taxes	38.87%	19.56%	19.08%
Software and IT Services Portfolio-Default | After Taxes on Distributions	34.71%	17.43%	16.84%
Software and IT Services Portfolio-Default | After Taxes on Distributions and Sales	25.44%	15.31%	15.37%
S&P 500® Index(reflects no deduction for fees, expenses, or taxes)	31.49%	11.70%	13.56%
MSCI U.S. IMI Software & Services 25-50 Index(reflects no deduction for fees, expenses, or taxes)	41.35%	20.04%	17.76%

[1] Differs from the ratios of expenses to average net assets in the Financial Highlights section of the prospectus because of acquired fund fees and expenses. For the period, acquired fund fees and expenses are less than 0.01% and are included in other expenses.

XML

Label

Element

Value

Risk/Return:

rr_RiskReturnAbstract

Registrant Name

dei_EntityRegistrantName

FIDELITY SELECT PORTFOLIOS

Prospectus Date

rr_ProspectusDate

Apr. 29, 2020

02.28 Select Portfolios: Group 4 Financials Sector Combo PRO-15 | Consumer Finance Portfolio

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: bold 12pt Arial, Helvetica, sans-serif;">Fund:<br/>Consumer Finance Portfolio</p>

Objective [Heading]

rr_ObjectiveHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks capital appreciation.

Expense [Heading]

rr_ExpenseHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

Shareholder Fees Caption [Text]

rr_ShareholderFeesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

(fees paid directly from your investment)

rr_ShareholderFeeOther

none

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

Portfolio Turnover [Text Block]

rr_PortfolioTurnoverTextBlock

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 20% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

20.00%

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Strategy [Heading]

rr_StrategyHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in providing products and services associated with consumer finance.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

Strategy Portfolio Concentration [Text]

rr_StrategyPortfolioConcentration

<font style="FONT-FAMILY: Times New Roman" size="3">Normally investing at least 80% of assets in securities of companies principally engaged in providing products and services associated with consumer finance.</font>

Risk [Heading]

rr_RiskHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Consumer Finance Industry Concentration. The consumer finance industry can be significantly affected by changing economic conditions, demand for consumer loans, refinancing activity, interest rate changes, and government regulation.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

Risk Lose Money [Text]

rr_RiskLoseMoney

<font style="FONT-FAMILY: Times New Roman" size="3">You could lose money by investing in the fund.</font>

Risk Nondiversified Status [Text]

rr_RiskNondiversifiedStatus

<font style="FONT-FAMILY: Times New Roman" size="3">In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.</font>

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

<font style="FONT-FAMILY: Times New Roman" size="3">An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</font>

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Prior to December 1, 2010, the fund was named Home Finance Portfolio, and the fund operated under certain different investment policies and compared its performance to a different additional index. The fund's historical performance may not represent its current investment policies. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

<font style="FONT-FAMILY: Times New Roman" size="3">The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time.</font>

Performance Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

<font style="FONT-FAMILY: Times New Roman" size="3">www.fidelity.com </font>

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

<font style="FONT-FAMILY: Times New Roman" size="3">Past performance (before and after taxes) is not an indication of future performance.</font>

Bar Chart [Heading]

rr_BarChartHeading

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	21.38%	March 31, 2012
Lowest Quarter Return	-15.24%	December 31, 2018
Year-to-Date Return	-41.08%	March 31, 2020

Performance Table Heading

rr_PerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

<font style="FONT-FAMILY: Times New Roman" size="3">After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes.</font>

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

<font style="FONT-FAMILY: Times New Roman" size="3">The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan).</font>

Performance Table Explanation after Tax Higher

rr_PerformanceTableExplanationAfterTaxHigher

<font style="FONT-FAMILY: Times New Roman" size="3">Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.</font>

Performance Table Narrative

rr_PerformanceTableNarrativeTextBlock

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

02.28 Select Portfolios: Group 4 Financials Sector Combo PRO-15 | Consumer Finance Portfolio | Consumer Finance Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Management fee

rr_ManagementFeesOverAssets

0.54%

Distribution and/or Service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

none

Other expenses

rr_OtherExpensesOverAssets

0.32%

Total annual operating expenses

rr_ExpensesOverAssets

0.86%

1 year

rr_ExpenseExampleYear01

$ 88

3 years

rr_ExpenseExampleYear03

274

5 years

rr_ExpenseExampleYear05

477

10 years

rr_ExpenseExampleYear10

$ 1,061

2010

rr_AnnualReturn2010

5.93%

2011

rr_AnnualReturn2011

(0.99%)

2012

rr_AnnualReturn2012

34.46%

2013

rr_AnnualReturn2013

32.57%

2014

rr_AnnualReturn2014

7.06%

2015

rr_AnnualReturn2015

(4.96%)

2016

rr_AnnualReturn2016

14.59%

2017

rr_AnnualReturn2017

23.11%

2018

rr_AnnualReturn2018

(10.39%)

2019

rr_AnnualReturn2019

34.18%

Year to Date Return, Label

rr_YearToDateReturnLabel

Year-to-Date Return

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Mar. 31, 2020

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

(41.08%)

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Highest Quarter Return

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Mar. 31, 2012

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

21.38%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Lowest Quarter Return

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Dec. 31, 2018

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(15.24%)

02.28 Select Portfolios: Group 4 Financials Sector Combo PRO-15 | Consumer Finance Portfolio | Return Before Taxes | Consumer Finance Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Consumer Finance Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return Before Taxes</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

34.18%

Past 5 years

rr_AverageAnnualReturnYear05

10.02%

Past 10 years

rr_AverageAnnualReturnYear10

12.43%

02.28 Select Portfolios: Group 4 Financials Sector Combo PRO-15 | Consumer Finance Portfolio | After Taxes on Distributions | Consumer Finance Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Consumer Finance Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

33.55%

Past 5 years

rr_AverageAnnualReturnYear05

8.63%

Past 10 years

rr_AverageAnnualReturnYear10

10.48%

02.28 Select Portfolios: Group 4 Financials Sector Combo PRO-15 | Consumer Finance Portfolio | After Taxes on Distributions and Sales | Consumer Finance Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Consumer Finance Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions and Sale of Fund Shares</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

20.56%

Past 5 years

rr_AverageAnnualReturnYear05

7.55%

Past 10 years

rr_AverageAnnualReturnYear10

9.65%

02.28 Select Portfolios: Group 4 Financials Sector Combo PRO-15 | Consumer Finance Portfolio | S&P 500® Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

31.49%

Past 5 years

rr_AverageAnnualReturnYear05

11.70%

Past 10 years

rr_AverageAnnualReturnYear10

13.56%

02.28 Select Portfolios: Group 4 Financials Sector Combo PRO-15 | Consumer Finance Portfolio | S&P® Consumer Finance Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

33.04%

Past 5 years

rr_AverageAnnualReturnYear05

8.85%

Past 10 years

rr_AverageAnnualReturnYear10

11.64%

XML

Label

Element

Value

Risk/Return:

rr_RiskReturnAbstract

Registrant Name

dei_EntityRegistrantName

FIDELITY SELECT PORTFOLIOS

Prospectus Date

rr_ProspectusDate

Apr. 29, 2020

02.28 Select Portfolios: Group 3 Energy Sector Combo PRO-13 | Natural Resources Portfolio

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: bold 12pt Arial, Helvetica, sans-serif;">Fund:<br/>Natural Resources Portfolio</p>

Objective [Heading]

rr_ObjectiveHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks capital appreciation.

Expense [Heading]

rr_ExpenseHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

Shareholder Fees Caption [Text]

rr_ShareholderFeesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

(fees paid directly from your investment)

rr_ShareholderFeeOther

none

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

Portfolio Turnover [Text Block]

rr_PortfolioTurnoverTextBlock

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 8% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

8.00%

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Strategy [Heading]

rr_StrategyHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

• Normally investing primarily in common stocks and in certain precious metals.

• Normally investing at least 80% of assets in securities of companies principally engaged in owning or developing natural resources, or supplying goods and services to such companies, and in precious metals.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

Strategy Portfolio Concentration [Text]

rr_StrategyPortfolioConcentration

<font style="FONT-FAMILY: Times New Roman" size="3">Normally investing at least 80% of assets in securities of companies principally engaged in owning or developing natural resources, or supplying goods and services to such companies, and in precious metals.</font>

Risk [Heading]

rr_RiskHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Geographic Concentration in Canada. Because the fund concentrates its investments in Canada, the fund's performance is expected to be closely tied to social, political, and economic conditions within Canada and to be more volatile than the performance of more geographically diversified funds. In addition, because the fund may invest a significant percentage of assets in certain industries, the fund's performance could be affected to the extent that the particular industry or industries in which the fund invests are sensitive to adverse social, political, economic, currency, or regulatory developments.

• Natural Resources Industry Concentration. The natural resources industries can be significantly affected by events relating to international political and economic developments, energy conservation, the success of exploration projects, commodity prices, and tax and other government regulations.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

Risk Lose Money [Text]

rr_RiskLoseMoney

<font style="FONT-FAMILY: Times New Roman" size="3">You could lose money by investing in the fund.</font>

Risk Nondiversified Status [Text]

rr_RiskNondiversifiedStatus

<font style="FONT-FAMILY: Times New Roman" size="3">In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.</font>

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

<font style="FONT-FAMILY: Times New Roman" size="3">An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</font>

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

<font style="FONT-FAMILY: Times New Roman" size="3">The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time.</font>

Performance Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

<font style="FONT-FAMILY: Times New Roman" size="3">www.fidelity.com </font>

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

<font style="FONT-FAMILY: Times New Roman" size="3">Past performance (before and after taxes) is not an indication of future performance.</font>

Bar Chart [Heading]

rr_BarChartHeading

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	24.75%	December 31, 2010
Lowest Quarter Return	-25.64%	September 30, 2011
Year-to-Date Return	-48.28%	March 31, 2020

Performance Table Heading

rr_PerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

<font style="FONT-FAMILY: Times New Roman" size="3">After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes.</font>

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

<font style="FONT-FAMILY: Times New Roman" size="3">The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan).</font>

Performance Table Explanation after Tax Higher

rr_PerformanceTableExplanationAfterTaxHigher

<font style="FONT-FAMILY: Times New Roman" size="3">Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.</font>

Performance Table Narrative

rr_PerformanceTableNarrativeTextBlock

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

02.28 Select Portfolios: Group 3 Energy Sector Combo PRO-13 | Natural Resources Portfolio | Natural Resources Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Management fee

rr_ManagementFeesOverAssets

0.54%

Distribution and/or Service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

none

Other expenses

rr_OtherExpensesOverAssets

0.30%

Total annual operating expenses

rr_ExpensesOverAssets

0.84%

1 year

rr_ExpenseExampleYear01

$ 86

3 years

rr_ExpenseExampleYear03

268

5 years

rr_ExpenseExampleYear05

466

10 years

rr_ExpenseExampleYear10

$ 1,037

2010

rr_AnnualReturn2010

23.09%

2011

rr_AnnualReturn2011

(9.25%)

2012

rr_AnnualReturn2012

3.35%

2013

rr_AnnualReturn2013

17.49%

2014

rr_AnnualReturn2014

(12.29%)

2015

rr_AnnualReturn2015

(21.64%)

2016

rr_AnnualReturn2016

30.24%

2017

rr_AnnualReturn2017

(0.10%)

2018

rr_AnnualReturn2018

(24.22%)

2019

rr_AnnualReturn2019

19.08%

Year to Date Return, Label

rr_YearToDateReturnLabel

Year-to-Date Return

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Mar. 31, 2020

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

(48.28%)

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Highest Quarter Return

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Dec. 31, 2010

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

24.75%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Lowest Quarter Return

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Sep. 30, 2011

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(25.64%)

02.28 Select Portfolios: Group 3 Energy Sector Combo PRO-13 | Natural Resources Portfolio | Return Before Taxes | Natural Resources Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Natural Resources Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return Before Taxes</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

19.08%

Past 5 years

rr_AverageAnnualReturnYear05

(1.66%)

Past 10 years

rr_AverageAnnualReturnYear10

0.91%

02.28 Select Portfolios: Group 3 Energy Sector Combo PRO-13 | Natural Resources Portfolio | After Taxes on Distributions | Natural Resources Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Natural Resources Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

18.67%

Past 5 years

rr_AverageAnnualReturnYear05

(1.91%)

Past 10 years

rr_AverageAnnualReturnYear10

0.54%

02.28 Select Portfolios: Group 3 Energy Sector Combo PRO-13 | Natural Resources Portfolio | After Taxes on Distributions and Sales | Natural Resources Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Natural Resources Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions and Sale of Fund Shares</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

11.57%

Past 5 years

rr_AverageAnnualReturnYear05

(1.26%)

Past 10 years

rr_AverageAnnualReturnYear10

0.74%

02.28 Select Portfolios: Group 3 Energy Sector Combo PRO-13 | Natural Resources Portfolio | S&P 500® Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

31.49%

Past 5 years

rr_AverageAnnualReturnYear05

11.70%

Past 10 years

rr_AverageAnnualReturnYear10

13.56%

02.28 Select Portfolios: Group 3 Energy Sector Combo PRO-13 | Natural Resources Portfolio | S&P® North American Natural Resources Sector Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

17.63%

Past 5 years

rr_AverageAnnualReturnYear05

(1.41%)

Past 10 years

rr_AverageAnnualReturnYear10

1.39%

XML

Total

02.28 Select Portfolios: Group 9 Telecommunications Services Sector Retail Combo PRO-13 | Telecommunications Portfolio

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: normal 12pt Arial, Helvetica, sans-serif;"><b>Fund/Class</b>:<br/><b>Telecommunications Portfolio</b>/Telecommunications Portfolio</p>

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

The fund seeks capital appreciation.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

Shareholder Fees {- Telecommunications Portfolio}	02.28 Select Portfolios: Group 9 Telecommunications Services Sector Retail Combo PRO-13 Telecommunications Portfolio USD ($)
(fees paid directly from your investment)	none

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Annual Operating Expenses {- Telecommunications Portfolio}	02.28 Select Portfolios: Group 9 Telecommunications Services Sector Retail Combo PRO-13 Telecommunications Portfolio Telecommunications Portfolio
Management fee	0.54%
Distribution and/or Service (12b-1) fees	none
Other expenses	0.29%
Total annual operating expenses	0.83%

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Expense Example {- Telecommunications Portfolio}	02.28 Select Portfolios: Group 9 Telecommunications Services Sector Retail Combo PRO-13 Telecommunications Portfolio Telecommunications Portfolio USD ($)
1 year	$ 85
3 years	265
5 years	460
10 years	$ 1,025

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 58% of the average value of its portfolio.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in the development, production, or distribution of telecommunications services.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Telecom Services Industry Concentration. The telecom services industry is subject to government regulation and can be significantly affected by intense competition and technology changes.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	17.58%	September 30, 2010
Lowest Quarter Return	-16.97%	September 30, 2011
Year-to-Date Return	-8.13%	March 31, 2020

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

Average Annual Total Returns{- Telecommunications Portfolio} - 02.28 Select Portfolios: Group 9 Telecommunications Services Sector Retail Combo PRO-13 - Telecommunications Portfolio	Past 1 year	Past 5 years	Past 10 years
Telecommunications Portfolio | Return Before Taxes	20.40%	7.19%	9.13%
Telecommunications Portfolio | After Taxes on Distributions	19.46%	5.46%	8.00%
Telecommunications Portfolio | After Taxes on Distributions and Sales	12.73%	5.40%	7.32%
S&P 500® Index(reflects no deduction for fees, expenses, or taxes)	31.49%	11.70%	13.56%
MSCI U.S. IM Telecommunication Services 25-50 Index(reflects no deduction for fees, expenses, or taxes)	12.64%	4.11%	7.99%

XML

Total

02.28 Select Portfolios: Group 8 Materials Sector Retail Combo PRO-15 | Gold Portfolio

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: normal 12pt Arial, Helvetica, sans-serif;"><b>Fund/Class</b>:<br/><b>Gold Portfolio</b>/Gold Portfolio</p>

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

The fund seeks capital appreciation.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

Shareholder Fees {- Gold Portfolio}	02.28 Select Portfolios: Group 8 Materials Sector Retail Combo PRO-15 Gold Portfolio USD ($)
(fees paid directly from your investment)	none

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Annual Operating Expenses {- Gold Portfolio}	02.28 Select Portfolios: Group 8 Materials Sector Retail Combo PRO-15 Gold Portfolio Gold Portfolio
Management fee	0.54%
Distribution and/or Service (12b-1) fees	none
Other expenses	0.25%
Total annual operating expenses	0.79%

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Expense Example {- Gold Portfolio}	02.28 Select Portfolios: Group 8 Materials Sector Retail Combo PRO-15 Gold Portfolio Gold Portfolio USD ($)
1 year	$ 81
3 years	252
5 years	439
10 years	$ 978

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 56% of the average value of its portfolio.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

• Normally investing primarily in common stocks and in certain precious metals.

• Investing primarily in companies engaged in exploration, mining, processing, or dealing in gold, or to a lesser degree, in silver, platinum, diamonds, or other precious metals and minerals.

• Normally investing at least 80% of assets in securities of companies principally engaged in gold-related activities, and in gold bullion or coins.

• Investing up to 25% of assets in gold and other precious metals through a wholly-owned subsidiary organized under the laws of the Cayman Islands.

• Potentially investing in other precious metals, instruments whose value is linked to the price of precious metals, and securities of companies that manufacture and distribute precious metal and minerals products (such as jewelry, watches, and metal foil and leaf) and companies that invest in other companies engaged in gold and other precious metal and mineral-related activities.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets, particularly emerging markets, can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market. Emerging markets can be subject to greater social, economic, regulatory, and political uncertainties and can be extremely volatile. Foreign exchange rates also can be extremely volatile.

• Geographic Concentration in Canada. Because an underlying fund concentrates its investments in Canada, the underlying fund's performance is expected to be closely tied to social, political, and economic conditions within Canada and to be more volatile than the performance of more geographically diversified funds. In addition, because the underlying fund may invest a significant percentage of assets in certain industries, the underlying fund's performance could be affected to the extent that the particular industry or industries in which the fund invests are sensitive to adverse social, political, economic, currency, or regulatory developments.

• Gold Industry Concentration. The gold industry can be significantly affected by international monetary and political developments such as currency devaluations or revaluations, central bank movements, economic and social conditions within a country, trade imbalances, or trade or currency restrictions between countries, as well as supply and demand for gold and operational costs associated with mining.

• Subsidiary Risk. Investment in Fidelity Select Gold Cayman Ltd., an unregistered subsidiary, is not subject to the investor protections of the Investment Company Act of 1940 (1940 Act) and is subject to the risks associated with the gold industry. Changes in tax and other laws could negatively affect investments in the subsidiary.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the 1940 Act, which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	41.04%	March 31, 2016
Lowest Quarter Return	-37.37%	June 30, 2013
Year-to-Date Return	-19.07%	March 31, 2020

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

Average Annual Total Returns{- Gold Portfolio} - 02.28 Select Portfolios: Group 8 Materials Sector Retail Combo PRO-15 - Gold Portfolio	Past 1 year	Past 5 years	Past 10 years
Gold Portfolio | Return Before Taxes	35.50%	9.14%	(3.75%)
Gold Portfolio | After Taxes on Distributions	35.41%	8.81%	(4.22%)
Gold Portfolio | After Taxes on Distributions and Sales	21.15%	7.09%	(2.61%)
S&P 500® Index(reflects no deduction for fees, expenses, or taxes)	31.49%	11.70%	13.56%
S&P® Global BMI Gold Capped 20/45 Linked Index(reflects no deduction for fees, expenses, or taxes)	45.04%	13.19%	(2.52%)

XML

Label

Element

Value

Risk/Return:

rr_RiskReturnAbstract

Registrant Name

dei_EntityRegistrantName

FIDELITY SELECT PORTFOLIOS

Prospectus Date

rr_ProspectusDate

Apr. 29, 2020

02.28 Select Portfolios: Group 1 Consumer Discretionary Sector Combo PRO-16 | Construction and Housing Portfolio

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: bold 12pt Arial, Helvetica, sans-serif;">Fund:<br/>Construction and Housing Portfolio</p>

Objective [Heading]

rr_ObjectiveHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks capital appreciation.

Expense [Heading]

rr_ExpenseHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

Shareholder Fees Caption [Text]

rr_ShareholderFeesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

(fees paid directly from your investment)

rr_ShareholderFeeOther

none

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

Portfolio Turnover [Text Block]

rr_PortfolioTurnoverTextBlock

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 161% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

161.00%

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Strategy [Heading]

rr_StrategyHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in the design and construction of residential, commercial, industrial, and public works facilities, as well as companies engaged in the manufacture, supply, distribution, or sale of construction and housing products or services.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

Strategy Portfolio Concentration [Text]

rr_StrategyPortfolioConcentration

<font style="FONT-FAMILY: Times New Roman" size="3">Normally investing at least 80% of assets in securities of companies principally engaged in the design and construction of residential, commercial, industrial, and public works facilities, as well as companies engaged in the manufacture, supply, distribution, or sale of construction and housing products or services.</font>

Risk [Heading]

rr_RiskHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Construction and Housing Industry Concentration. The construction and housing industry can be significantly affected by changes in housing starts, the level of new and existing home sales, government spending, public works, interest rates, consumer confidence and spending, taxation, and demographic patterns.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

• High Portfolio Turnover. High portfolio turnover (more than 100%) may result in increased transaction costs and potentially higher capital gains or losses. The effects of higher than normal portfolio turnover may adversely affect the fund's performance.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

Risk Lose Money [Text]

rr_RiskLoseMoney

<font style="FONT-FAMILY: Times New Roman" size="3">You could lose money by investing in the fund.</font>

Risk Nondiversified Status [Text]

rr_RiskNondiversifiedStatus

<font style="FONT-FAMILY: Times New Roman" size="3">In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.</font>

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

<font style="FONT-FAMILY: Times New Roman" size="3">An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</font>

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

<font style="FONT-FAMILY: Times New Roman" size="3">The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time.</font>

Performance Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

<font style="FONT-FAMILY: Times New Roman" size="3">www.fidelity.com </font>

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

<font style="FONT-FAMILY: Times New Roman" size="3">Past performance (before and after taxes) is not an indication of future performance.</font>

Bar Chart [Heading]

rr_BarChartHeading

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	24.65%	December 31, 2011
Lowest Quarter Return	-19.41%	September 30, 2011
Year-to-Date Return	-25.74%	March 31, 2020

Performance Table Heading

rr_PerformanceTableHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

<font style="FONT-FAMILY: Times New Roman" size="3">After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes.</font>

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

<font style="FONT-FAMILY: Times New Roman" size="3">The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan).</font>

Performance Table Explanation after Tax Higher

rr_PerformanceTableExplanationAfterTaxHigher

<font style="FONT-FAMILY: Times New Roman" size="3">Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.</font>

Performance Table Narrative

rr_PerformanceTableNarrativeTextBlock

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

02.28 Select Portfolios: Group 1 Consumer Discretionary Sector Combo PRO-16 | Construction and Housing Portfolio | Construction and Housing Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Management fee

rr_ManagementFeesOverAssets

0.54%

Distribution and/or Service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

none

Other expenses

rr_OtherExpensesOverAssets

0.25%

Total annual operating expenses

rr_ExpensesOverAssets

0.79%

1 year

rr_ExpenseExampleYear01

$ 81

3 years

rr_ExpenseExampleYear03

252

5 years

rr_ExpenseExampleYear05

439

10 years

rr_ExpenseExampleYear10

$ 978

2010

rr_AnnualReturn2010

21.54%

2011

rr_AnnualReturn2011

2.89%

2012

rr_AnnualReturn2012

38.01%

2013

rr_AnnualReturn2013

21.25%

2014

rr_AnnualReturn2014

15.74%

2015

rr_AnnualReturn2015

6.91%

2016

rr_AnnualReturn2016

5.05%

2017

rr_AnnualReturn2017

26.14%

2018

rr_AnnualReturn2018

(15.59%)

2019

rr_AnnualReturn2019

41.07%

Year to Date Return, Label

rr_YearToDateReturnLabel

Year-to-Date Return

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Mar. 31, 2020

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

(25.74%)

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Highest Quarter Return

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Dec. 31, 2011

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

24.65%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Lowest Quarter Return

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Sep. 30, 2011

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(19.41%)

02.28 Select Portfolios: Group 1 Consumer Discretionary Sector Combo PRO-16 | Construction and Housing Portfolio | Return Before Taxes | Construction and Housing Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Construction and Housing Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return Before Taxes</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

41.07%

Past 5 years

rr_AverageAnnualReturnYear05

11.02%

Past 10 years

rr_AverageAnnualReturnYear10

15.11%

02.28 Select Portfolios: Group 1 Consumer Discretionary Sector Combo PRO-16 | Construction and Housing Portfolio | After Taxes on Distributions | Construction and Housing Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Construction and Housing Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

38.10%

Past 5 years

rr_AverageAnnualReturnYear05

8.82%

Past 10 years

rr_AverageAnnualReturnYear10

13.38%

02.28 Select Portfolios: Group 1 Consumer Discretionary Sector Combo PRO-16 | Construction and Housing Portfolio | After Taxes on Distributions and Sales | Construction and Housing Portfolio-Default

Risk/Return:

rr_RiskReturnAbstract

Column

rr_AverageAnnualReturnColumnName

Construction and Housing Portfolio

Label

rr_AverageAnnualReturnLabel

<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions and Sale of Fund Shares</b></font>

Past 1 year

rr_AverageAnnualReturnYear01

25.67%

Past 5 years

rr_AverageAnnualReturnYear05

8.35%

Past 10 years

rr_AverageAnnualReturnYear10

12.36%

02.28 Select Portfolios: Group 1 Consumer Discretionary Sector Combo PRO-16 | Construction and Housing Portfolio | S&P 500® Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

31.49%

Past 5 years

rr_AverageAnnualReturnYear05

11.70%

Past 10 years

rr_AverageAnnualReturnYear10

13.56%

02.28 Select Portfolios: Group 1 Consumer Discretionary Sector Combo PRO-16 | Construction and Housing Portfolio | MSCI U.S. IMI Construction & Housing 25-50 Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

Past 1 year

rr_AverageAnnualReturnYear01

36.61%

Past 5 years

rr_AverageAnnualReturnYear05

12.90%

Past 10 years

rr_AverageAnnualReturnYear10

15.82%

XML

Label

Element

Value

Risk/Return:

rr_RiskReturnAbstract

Registrant Name

dei_EntityRegistrantName

FIDELITY SELECT PORTFOLIOS

Prospectus Date

rr_ProspectusDate

Apr. 29, 2020

02.28 Select Portfolios: Group 5 Health Care Sector Combo PRO-13 | Biotechnology Portfolio

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: bold 12pt Arial, Helvetica, sans-serif;">Fund:<br/>Biotechnology Portfolio</p>

Objective [Heading]

rr_ObjectiveHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks capital appreciation.

Expense [Heading]

rr_ExpenseHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

Shareholder Fees Caption [Text]

rr_ShareholderFeesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

(fees paid directly from your investment)

rr_ShareholderFeeOther

none

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

Portfolio Turnover [Text Block]

rr_PortfolioTurnoverTextBlock

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 50% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

50.00%

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Strategy [Heading]

rr_StrategyHeading

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

Strategy Narrative [Text Block]

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• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in the research, development, manufacture, and distribution of various biotechnological products, services, and processes and companies that benefit significantly from scientific and technological advances in biotechnology.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

Strategy Portfolio Concentration [Text]

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<font style="FONT-FAMILY: Times New Roman" size="3">Normally investing at least 80% of assets in securities of companies principally engaged in the research, development, manufacture, and distribution of various biotechnological products, services, and processes and companies that benefit significantly from scientific and technological advances in biotechnology.</font>

Risk [Heading]

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<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

Risk Narrative [Text Block]

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• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Biotechnology Industry Concentration. The biotechnology industry can be significantly affected by patent considerations, intense competition, rapid technological change and obsolescence, and government regulation, and revenue patterns can be erratic.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

Risk Lose Money [Text]

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<font style="FONT-FAMILY: Times New Roman" size="3">You could lose money by investing in the fund.</font>

Risk Nondiversified Status [Text]

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<font style="FONT-FAMILY: Times New Roman" size="3">In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.</font>

Risk Not Insured Depository Institution [Text]

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<font style="FONT-FAMILY: Times New Roman" size="3">An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</font>

Bar Chart and Performance Table [Heading]

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<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

Performance Narrative [Text Block]

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The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

<font style="FONT-FAMILY: Times New Roman" size="3">The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time.</font>

Performance Availability Website Address [Text]

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<font style="FONT-FAMILY: Times New Roman" size="3">www.fidelity.com</font>

Performance Past Does Not Indicate Future [Text]

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<font style="FONT-FAMILY: Times New Roman" size="3">Past performance (before and after taxes) is not an indication of future performance.</font>

Bar Chart [Heading]

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<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

Bar Chart Closing [Text Block]

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During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	26.57%	December 31, 2019
Lowest Quarter Return	-28.45%	March 31, 2016
Year-to-Date Return	-14.71%	March 31, 2020

Performance Table Heading

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<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

Performance Table Uses Highest Federal Rate

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<font style="FONT-FAMILY: Times New Roman" size="3">After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes.</font>

Performance Table Not Relevant to Tax Deferred

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<font style="FONT-FAMILY: Times New Roman" size="3">The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan).</font>

Performance Table Explanation after Tax Higher

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<font style="FONT-FAMILY: Times New Roman" size="3">Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.</font>

Performance Table Narrative

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After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

02.28 Select Portfolios: Group 5 Health Care Sector Combo PRO-13 | Biotechnology Portfolio | Biotechnology Portfolio-Default

Risk/Return:

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Management fee

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0.54%

Distribution and/or Service (12b-1) fees

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none

Other expenses

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0.18%

Total annual operating expenses

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0.72%

1 year

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$ 74

3 years

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230

5 years

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401

10 years

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$ 894

2010

rr_AnnualReturn2010

11.41%

2011

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18.18%

2012

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36.59%

2013

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65.66%

2014

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35.05%

2015

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13.67%

2016

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(23.72%)

2017

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27.87%

2018

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(10.73%)

2019

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35.96%

Year to Date Return, Label

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Year-to-Date Return

Bar Chart, Year to Date Return, Date

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Mar. 31, 2020

Bar Chart, Year to Date Return

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(14.71%)

Highest Quarterly Return, Label

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Highest Quarter Return

Highest Quarterly Return, Date

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Dec. 31, 2019

Highest Quarterly Return

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26.57%

Lowest Quarterly Return, Label

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Lowest Quarter Return

Lowest Quarterly Return, Date

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Mar. 31, 2016

Lowest Quarterly Return

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(28.45%)

02.28 Select Portfolios: Group 5 Health Care Sector Combo PRO-13 | Biotechnology Portfolio | Return Before Taxes | Biotechnology Portfolio-Default

Risk/Return:

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Column

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Biotechnology Portfolio

Label

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<font style="FONT-FAMILY: Times New Roman" ><b>Return Before Taxes</b></font>

Past 1 year

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35.96%

Past 5 years

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6.12%

Past 10 years

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18.40%

02.28 Select Portfolios: Group 5 Health Care Sector Combo PRO-13 | Biotechnology Portfolio | After Taxes on Distributions | Biotechnology Portfolio-Default

Risk/Return:

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Column

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Biotechnology Portfolio

Label

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<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions</b></font>

Past 1 year

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33.19%

Past 5 years

rr_AverageAnnualReturnYear05

4.64%

Past 10 years

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17.16%

02.28 Select Portfolios: Group 5 Health Care Sector Combo PRO-13 | Biotechnology Portfolio | After Taxes on Distributions and Sales | Biotechnology Portfolio-Default

Risk/Return:

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Column

rr_AverageAnnualReturnColumnName

Biotechnology Portfolio

Label

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<font style="FONT-FAMILY: Times New Roman" ><b>Return After Taxes on Distributions and Sale of Fund Shares</b></font>

Past 1 year

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23.15%

Past 5 years

rr_AverageAnnualReturnYear05

4.60%

Past 10 years

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15.62%

02.28 Select Portfolios: Group 5 Health Care Sector Combo PRO-13 | Biotechnology Portfolio | S&P 500® Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

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Past 1 year

rr_AverageAnnualReturnYear01

31.49%

Past 5 years

rr_AverageAnnualReturnYear05

11.70%

Past 10 years

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13.56%

02.28 Select Portfolios: Group 5 Health Care Sector Combo PRO-13 | Biotechnology Portfolio | MSCI U.S. IMI Biotechnology 25-50 Index(reflects no deduction for fees, expenses, or taxes)

Risk/Return:

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Past 1 year

rr_AverageAnnualReturnYear01

21.12%

Past 5 years

rr_AverageAnnualReturnYear05

6.33%

Past 10 years

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18.27%

XML

Total

02.28 Select Portfolios: Group 2 Consumer Staples Sector Retail PRO-11 | Consumer Staples Portfolio

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: normal 12pt Arial, Helvetica, sans-serif;"><b>Fund/Class</b>:<br/><b>Consumer Staples Portfolio</b>/Consumer Staples Portfolio</p>

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

The fund seeks capital appreciation.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

Shareholder Fees {- Consumer Staples Portfolio}	02.28 Select Portfolios: Group 2 Consumer Staples Sector Retail PRO-11 Consumer Staples Portfolio USD ($)
(fees paid directly from your investment)	none

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Annual Operating Expenses {- Consumer Staples Portfolio}	02.28 Select Portfolios: Group 2 Consumer Staples Sector Retail PRO-11 Consumer Staples Portfolio Consumer Staples Portfolio
Management fee	0.54%
Distribution and/or Service (12b-1) fees	none
Other expenses	0.21%
Total annual operating expenses	0.75%

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Expense Example {- Consumer Staples Portfolio}	02.28 Select Portfolios: Group 2 Consumer Staples Sector Retail PRO-11 Consumer Staples Portfolio Consumer Staples Portfolio USD ($)
1 year	$ 77
3 years	240
5 years	417
10 years	$ 930

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 40% of the average value of its portfolio.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in the manufacture, sale, or distribution of consumer staples.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.

• Consumer Staples Industry Concentration. The consumer staples industries can be significantly affected by demographics and product trends, competitive pricing, food fads, marketing campaigns, environmental factors, government regulation, the performance of the overall economy, interest rates, consumer confidence, and the cost of commodities.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	17.22%	March 31, 2019
Lowest Quarter Return	-10.53%	December 31, 2018
Year-to-Date Return	-16.58%	March 31, 2020

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

Average Annual Total Returns{- Consumer Staples Portfolio} - 02.28 Select Portfolios: Group 2 Consumer Staples Sector Retail PRO-11 - Consumer Staples Portfolio	Past 1 year	Past 5 years	Past 10 years
Consumer Staples Portfolio | Return Before Taxes	31.77%	5.48%	10.20%
Consumer Staples Portfolio | After Taxes on Distributions	30.92%	3.68%	8.75%
Consumer Staples Portfolio | After Taxes on Distributions and Sales	19.41%	4.05%	8.21%
S&P 500® Index(reflects no deduction for fees, expenses, or taxes)	31.49%	11.70%	13.56%
MSCI U.S. IMI Consumer Staples 25-50 Index(reflects no deduction for fees, expenses, or taxes)	26.20%	8.03%	12.25%

XML

Total

02.28 Select Portfolios: Group 7 Information Technology Sector Combo PRO-16 | Computers Portfolio

<p style="font: bold 20pt Arial, Helvetica, sans-serif;">Fund Summary</p><p style="font: bold 12pt Arial, Helvetica, sans-serif;">Fund:<br/>Computers Portfolio</p>

<font style="font: bold 16pt Arial, Helvetica, sans-serif;">Investment Objective</font>

The fund seeks capital appreciation.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Fee Table</b></font>

The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Shareholder fees</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px"></p>

Shareholder Fees {- Computers Portfolio}	02.28 Select Portfolios: Group 7 Information Technology Sector Combo PRO-16 Computers Portfolio USD ($)
(fees paid directly from your investment)	none

<p style="font: bold 11pt Arial, sans-serif; margin-bottom: 0px;">Annual Operating Expenses</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">(expenses that you pay each year as a % of the value of your investment)</p>

Annual Operating Expenses {- Computers Portfolio}	02.28 Select Portfolios: Group 7 Information Technology Sector Combo PRO-16 Computers Portfolio Computers Portfolio-Default
Management fee	0.54%
Distribution and/or Service (12b-1) fees	none
Other expenses	0.22%
Total annual operating expenses	0.76%

This example helps compare the cost of investing in the fund with the cost of investing in other funds.

Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:

<p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Sell All Shares</p>

Expense Example {- Computers Portfolio}	02.28 Select Portfolios: Group 7 Information Technology Sector Combo PRO-16 Computers Portfolio Computers Portfolio-Default USD ($)
1 year	$ 78
3 years	243
5 years	422
10 years	$ 942

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Portfolio Turnover</b></font>

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 116% of the average value of its portfolio.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Strategies</b></font>

• Normally investing primarily in common stocks.

• Normally investing at least 80% of assets in securities of companies principally engaged in research, design, development, manufacture, or distribution of products, processes, or services that relate to currently available or experimental hardware technology within the computer industry.

• Investing in domestic and foreign issuers.

• Using fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Principal Investment Risks</b></font>

• Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.

• Foreign Exposure. Foreign markets, particularly emerging markets, can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market. Emerging markets can be subject to greater social, economic, regulatory, and political uncertainties and can be extremely volatile.

• Geographic Concentration in Japan. Because the fund concentrates its investments in Japan, the fund's performance is expected to be closely tied to social, political, and economic conditions within Japan and to be more volatile than the performance of more geographically diversified funds.

• Computer Industry Concentration. The computer industry can be significantly affected by competitive pressures, changing domestic and international demand, research and development costs, availability and price of components, and product obsolescence.

• Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.

• High Portfolio Turnover. High portfolio turnover (more than 100%) may result in increased transaction costs and potentially higher capital gains or losses. The effects of higher than normal portfolio turnover may adversely affect the fund's performance.

In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.

An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the fund.

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Performance</b></font>

The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index and an additional index over various periods of time. The indexes have characteristics relevant to the fund's investment strategies. Index descriptions appear in the "Additional Index Information" section of the prospectus. Past performance (before and after taxes) is not an indication of future performance.

Visit www.fidelity.com for more recent performance information.

<p style="font:bold 11pt Arial, sans-serif; margin-bottom: 0px;">Year-by-Year Returns</p><p style="font: bold 9pt Arial, sans-serif; margin-top: 0px">Calendar Years</p>

During the periods shown in the chart:	Returns	Quarter ended
Highest Quarter Return	25.29%	March 31, 2012
Lowest Quarter Return	-19.07%	December 31, 2018
Year-to-Date Return	-14.95%	March 31, 2020

<font style="font: bold 16pt Arial, Helvetica, sans-serif;"><b>Average Annual Returns</b></font>

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement, such as an employee benefit plan (profit sharing, 401(k), or 403(b) plan). Return After Taxes on Distributions and Sale of Fund Shares may be higher than other returns for the same period due to a tax benefit of realizing a capital loss upon the sale of fund shares.

For the periods ended December 31, 2019

Average Annual Total Returns{- Computers Portfolio} - 02.28 Select Portfolios: Group 7 Information Technology Sector Combo PRO-16 - Computers Portfolio	Past 1 year	Past 5 years	Past 10 years
Computers Portfolio-Default | Return Before Taxes	40.04%	11.97%	13.59%
Computers Portfolio-Default | After Taxes on Distributions	35.84%	9.12%	11.84%
Computers Portfolio-Default | After Taxes on Distributions and Sales	25.94%	8.88%	10.95%
S&P 500® Index(reflects no deduction for fees, expenses, or taxes)	31.49%	11.70%	13.56%
FactSet Computers & Peripherals Linked Index(reflects no deduction for fees, expenses, or taxes)	38.75%	7.56%	10.78%