485BPOS

As filed with the U.S. Securities and Exchange Commission on February 16, 2018

File No. 033-22821
File No. 811-05601

U.S. SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

FORM N-1A

REGISTRATION STATEMENT UNDER THE
SECURITIES ACT OF 1933 o

POST-EFFECTIVE AMENDMENT NO. 72 x

and

REGISTRATION STATEMENT UNDER THE
INVESTMENT COMPANY ACT OF 1940 o

AMENDMENT NO. 73 x

SEI INSTITUTIONAL INTERNATIONAL TRUST
(Formerly, “SEI International Trust”)
(Exact Name of Registrant as Specified in Charter)

SEI Investments Company
One Freedom Valley Drive
Oaks, Pennsylvania 19456
(Address of Principal Executive Offices)

(610)-676-1000

(Registrant’s Telephone Number)

Timothy D. Barto, Esq.
SEI Investments Company
One Freedom Valley Drive
Oaks, Pennsylvania 19456
(Name and Address of Agent for Service)

Copy to:

Timothy W. Levin, Esq.

Morgan, Lewis & Bockius LLP

1701 Market Street

Philadelphia, Pennsylvania 19103

Title of Securities Being Registered...Units of Beneficial Interest

It is proposed that this filing will become effective (check appropriate box)

x immediately upon filing pursuant to paragraph (b)
o on [date] pursuant to paragraph (b)
o 60 days after filing pursuant to paragraph (a)(1)
o on [date] pursuant to paragraph (a)(1)
o 75 days after filing pursuant to paragraph (a)(2)
o on [date] pursuant to paragraph (a)(2) of Rule 485.

If appropriate, check the following box:

o This Post-Effective Amendment designates a new effective date for a previously filed Post-Effective Amendment.

SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, as amended, and the Investment Company Act of 1940, as amended, the Registrant certifies that it meets all of the requirements for effectiveness of this Registration Statement pursuant to Rule 485(b) under the Securities Act of 1933, as amended, and has duly caused this Post-Effective Amendment No. 72 to Registration Statement No. 033-22821 to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Oaks, Commonwealth of Pennsylvania on the 16th day of February, 2018.

SEI INSTITUTIONAL INTERNATIONAL TRUST
By:	/s/ Robert A. Nesher
Robert A. Nesher
Trustee, President & Chief Executive Officer

Pursuant to the requirements of the Securities Act of 1933, as amended, this Amendment to the Registration Statement has been signed below by the following persons in the capacities and on the date(s) indicated.

*		Trustee	February 16, 2018
William M. Doran
*		Trustee	February 16, 2018
George J. Sullivan, Jr.
*		Trustee	February 16, 2018
Nina Lesavoy
*		Trustee	February 16, 2018
James M. Williams
*		Trustee	February 16, 2018
Mitchell A. Johnson
*		Trustee	February 16, 2018
Hubert L. Harris, Jr.
*		Trustee	February 16, 2018
Susan C. Cote
/s/ Robert A. Nesher		Trustee, President & Chief Executive Officer	February 16, 2018
Robert A. Nesher
/s/ James Hoffmayer		Controller & Chief Financial Officer	February 16, 2018
James Hoffmayer
*By:	/s/ Robert A. Nesher
	Robert A. Nesher
	Attorney-in-Fact

INDEX TO EXHIBITS

EXHIBIT NO.	DESCRIPTION OF EXHIBIT	PAGE NO.
	Risk/return summary of the Funds’ prospectuses as an Interactive Data File using eXtensible Business Reporting Language (“XBRL”)

XML

Document and Entity Information	Total
Prospectus:
Document Type	485BPOS
Document Period End Date	Sep. 30, 2017
Registrant Name	SEI INSTITUTIONAL INTERNATIONAL TRUST
Central Index Key	0000835597
Amendment Flag	false
Document Creation Date	Jan. 26, 2018
Document Effective Date	Jan. 31, 2018
Prospectus Date	Jan. 31, 2018
Class F Prospectus | SIT INTERNATIONAL EQUITY FUND | SIT INTERNATIONAL EQUITY FUND - CLASS F, effective 1-31-2017 (formerly Class A)
Prospectus:
Trading Symbol	SEITX
Class F Prospectus | SIT EMERGING MARKETS EQUITY FUND | SIT EMERGING MARKETS EQUITY FUND - CLASS F, effective 1-31-2017 (formerly Class A)
Prospectus:
Trading Symbol	SIEMX
Class F Prospectus | SIT INTERNATIONAL FIXED INCOME FUND | SIT INTERNATIONAL FIXED INCOME FUND - CLASS F, effective 1-31-2017 (formerly Class A)
Prospectus:
Trading Symbol	SEFIX
Class F Prospectus | SIT EMERGING MARKETS DEBT FUND | SIT EMERGING MARKETS DEBT FUND - CLASS F, effective 1-31-2017 (formerly Class A)
Prospectus:
Trading Symbol	SITEX
Class I Prospectus | SIT INTERNATIONAL EQUITY FUND | SIT INTERNATIONAL EQUITY FUND - CLASS I
Prospectus:
Trading Symbol	SEEIX
Class Y Prospectus | SIT INTERNATIONAL EQUITY FUND | Class Y
Prospectus:
Trading Symbol	SEFCX
Class Y Prospectus | SIT EMERGING MARKETS EQUITY FUND | Class Y
Prospectus:
Trading Symbol	SEQFX
Class Y Prospectus | SIT INTERNATIONAL FIXED INCOME FUND | Class Y
Prospectus:
Trading Symbol	SIFIX
Class Y Prospectus | SIT EMERGING MARKETS DEBT FUND | Class Y
Prospectus:
Trading Symbol	SIEDX

XML

Class F Prospectus | SIT INTERNATIONAL EQUITY FUND

SIT INTERNATIONAL EQUITY FUND

Investment Goal

Long-term capital appreciation.

Fees and Expenses

The following tables describe the fees and expenses that you may pay if you buy and hold Fund shares.

ANNUAL FUND OPERATING EXPENSES (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses	Class F Prospectus SIT INTERNATIONAL EQUITY FUND SIT INTERNATIONAL EQUITY FUND - CLASS F, effective 1-31-2017 (formerly Class A)
Management Fees	0.51%
Distribution (12b-1) Fees	none
Other Expenses	0.64%
Total Annual Fund Operating Expenses	1.15%

EXAMPLE

This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Fund's operating expenses remain the same.

Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Expense Example	1 Year	3 Years	5 Years	10 Years
Class F Prospectus | SIT INTERNATIONAL EQUITY FUND | SIT INTERNATIONAL EQUITY FUND - CLASS F, effective 1-31-2017 (formerly Class A) | USD ($)	117	365	633	1,398

PORTFOLIO TURNOVER

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 Fund operating expenses or in the Example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 57% of the average value of its portfolio.

Principal Investment Strategies

Under normal circumstances, the International Equity Fund will invest at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in equity securities. Equity securities may include common stocks, preferred stock, warrants, participation notes and depositary receipts. The Fund will invest primarily in equity securities of issuers of all capitalization ranges that are located in at least three countries other than the U.S. It is expected that at least 40% of the Fund's assets will be invested outside the U.S. The Fund will invest primarily in companies located in developed countries, but may also invest in companies located in emerging markets. Generally, the Fund will invest less than 20% of its assets in emerging markets. Emerging market countries are those countries that are: (i) characterized as developing or emerging by any of the World Bank, the United Nations, the International Finance Corporation, or the European Bank for Reconstruction and Development; (ii) included in an emerging markets index by a recognized index provider; or (iii) countries with similar developing or emerging characteristics as countries classified as emerging market countries pursuant to sub-paragraph (i) and (ii) above, in each case determined at the time of purchase.

The Fund uses a multi-manager approach, relying upon a number of sub-advisers (each, a Sub-Adviser and collectively, the Sub-Advisers) with differing investment philosophies to manage portions of the Fund's portfolio under the general supervision of SEI Investments Management Corporation (SIMC), the Fund's adviser.

The Fund may invest in futures contracts, forward contracts and options for hedging purposes, including seeking to manage the Fund's currency exposure to foreign securities and mitigate the Fund's overall risk.

The Fund may purchase futures contracts or shares of exchange-traded funds (ETFs) to gain exposure to a particular portion of the market while awaiting an opportunity to purchase securities or other instruments directly.

Principal Risks

Credit Risk — The risk that the issuer of a security or the counterparty to a contract will default or otherwise become unable to honor a financial obligation.

Currency Risk — As a result of the Fund's investments in securities denominated in, and/or receiving revenues in, foreign currencies, the Fund will be subject to currency risk. Currency risk is the risk that foreign currencies will decline in value relative to the U.S. dollar or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency hedged. In either event, the dollar value of an investment in the Fund would be adversely affected. Currency exchange rates may fluctuate in response to, among other things, changes in interest rates, intervention (or failure to intervene) by U.S. or foreign governments, central banks or supranational entities, or by the imposition of currency controls or other political developments in the United States or abroad.

Depositary Receipts Risk — Depositary receipts, such as American Depositary Receipts (ADRs), are certificates evidencing ownership of shares of a foreign issuer that are issued by depositary banks and generally trade on an established market. Depositary receipts are subject to many of the risks associated with investing directly in foreign securities, including, among other things, political, social and economic developments abroad, currency movements and different legal, regulatory and tax environments.

Derivatives Risk — The Fund's use of futures contracts, forward contracts and options is subject to market risk, leverage risk, correlation risk and liquidity risk. Leverage risk, liquidity risk and market risk are described below. Many over-the-counter (OTC) derivative instruments will not have liquidity beyond the counterparty to the instrument. Correlation risk is the risk that changes in the value of the derivative may not correlate perfectly with the underlying asset, rate or index. The Fund's use of forward contracts is also subject to credit risk and valuation risk. Valuation risk is the risk that the derivative may be difficult to value and/or valued incorrectly. Credit risk is described above. Each of the above risks could cause the Fund to lose more than the principal amount invested in a derivative instrument. Some derivatives have the potential for unlimited loss, regardless of the size of the Fund's initial investment. The other parties to certain derivative contracts present the same types of credit risk as issuers of fixed income securities. The Fund's use of derivatives may also increase the amount of taxes payable by shareholders. Both U.S. and non-U.S. regulators are in the process of adopting and implementing regulations governing derivatives markets, the ultimate impact of which remains unclear.

Equity Market Risk — The risk that stock prices will fall over short or extended periods of time.

Exchange-Traded Funds (ETFs) Risk — The risks of owning shares of an ETF generally reflect the risks of owning the underlying securities the ETF is designed to track, although lack of liquidity in an ETF could result in its value being more volatile than the underlying portfolio securities. When the Fund invests in an ETF, in addition to directly bearing the expenses associated with its own operations, it will bear a pro rata portion of the ETF's expenses.

Foreign Investment/Emerging Markets Risk — The risk that non-U.S. securities may be subject to additional risks due to, among other things, political, social and economic developments abroad, currency movements and different legal, regulatory and tax environments. These additional risks may be heightened with respect to emerging market countries because political turmoil and rapid changes in economic conditions are more likely to occur in these countries.

Investment Style Risk — The risk that developed international equity securities may underperform other segments of the equity markets or the equity markets as a whole.

Leverage Risk — The Fund's use of derivatives may result in the Fund's total investment exposure substantially exceeding the value of its portfolio securities and the Fund's investment returns depending substantially on the performance of securities that the Fund may not directly own. The use of leverage can amplify the effects of market volatility on the Fund's share price and may also cause the Fund to liquidate portfolio positions when it would not be advantageous to do so in order to satisfy its obligations. The Fund's use of leverage may result in a heightened risk of investment loss.

Liquidity Risk — The risk that certain securities may be difficult or impossible to sell at the time and the price that the Fund would like. The Fund may have to lower the price of the security, sell other securities instead or forego an investment opportunity, any of which could have a negative effect on Fund management or performance.

Market Risk — The risk that the market value of a security may move up and down, sometimes rapidly and unpredictably. Market risk may affect a single issuer, an industry, a sector or the equity or bond market as a whole.

Participation Notes (P-Notes) Risk — P-Notes are participation interest notes that are issued by banks or broker-dealers and are designed to offer a return linked to a particular underlying equity, debt, currency or market. Investments in P-Notes involve the same risks associated with a direct investment in the underlying foreign companies or foreign securities markets that they seek to replicate. However, there can be no assurance that the trading price of P-Notes will equal the underlying value of the foreign companies or foreign securities markets that they seek to replicate.

Small and Medium Capitalization Risk — The risk that small and medium capitalization companies in which the Fund may invest may be more vulnerable to adverse business or economic events than larger, more established companies. In particular, small and medium capitalization companies may have limited product lines, markets and financial resources and may depend upon a relatively small management group. Therefore, small capitalization and medium capitalization stocks may be more volatile than those of larger companies. Small capitalization and medium capitalization stocks may be traded OTC or listed on an exchange.

Warrants Risk — Warrants are instruments that entitle the holder to buy an equity security at a specific price for a specific period of time. Warrants may be more speculative than other types of investments. The price of a warrant may be more volatile than the price of its underlying security, and a warrant may offer greater potential for capital appreciation as well as capital loss. A warrant ceases to have value if it is not exercised prior to its expiration date.

Investing in the Fund involves risk, and there is no guarantee that the Fund will achieve its investment goal. You could lose money on your investment in the Fund, just as you could with other investments. 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.

Performance Information

The bar chart and the performance table below provide some indication of the risks of investing in the Fund by showing changes in the Fund's performance from year to year for the past ten calendar years and by showing how the Fund's average annual returns for 1, 5 and 10 years, and since the Fund's inception, compare with those of a broad measure of market performance. The performance information shown is based on full calendar years. The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future. For current performance information, please call 1-800-DIAL-SEI.

Best Quarter: 22.98% (06/30/09)
Worst Quarter: -26.13% (09/30/08)

Average Annual Total Returns (for the periods ended December 31, 2017)

After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Your actual after-tax returns will depend on your tax situation and may differ from those shown. After-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts.

Average Annual Returns - Class F Prospectus - SIT INTERNATIONAL EQUITY FUND	Label	Average Annual Returns, 1 Year	Average Annual Returns, 5 Years	Average Annual Returns, 10 Years	Average Annual Returns, Since Inception		Average Annual Returns, Inception Date
SIT INTERNATIONAL EQUITY FUND - CLASS F, effective 1-31-2017 (formerly Class A)	Return Before Taxes	26.66%	7.91%	none	3.90%		Dec. 20, 1989
After Taxes on Distributions | SIT INTERNATIONAL EQUITY FUND - CLASS F, effective 1-31-2017 (formerly Class A)	Return After Taxes on Distributions	25.95%	7.54%	(0.21%)	3.12%
After Taxes on Distributions and Sale of Fund Shares | SIT INTERNATIONAL EQUITY FUND - CLASS F, effective 1-31-2017 (formerly Class A)	Return After Taxes on Distributions and Sale of Fund Shares	15.08%	6.16%	0.03%	3.03%
MSCI EAFE Index Return (reflects no deduction for fees, expenses or taxes)	MSCI EAFE Index Return (reflects no deduction for fees, expenses or taxes)	25.03%	7.90%	1.94%	4.68%	[1]	Dec. 31, 1989

[1] Index returns are shown from December 31, 1989.

XML

Label

Element

Value

Class F Prospectus | SIT INTERNATIONAL EQUITY FUND

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

SIT INTERNATIONAL EQUITY FUND

Objective [Heading]

rr_ObjectiveHeading

Investment Goal

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

Long-term capital appreciation.

Expense [Heading]

rr_ExpenseHeading

Fees and Expenses

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

The following tables describe the fees and expenses that you may pay if you buy and hold Fund shares.

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

ANNUAL FUND OPERATING EXPENSES (expenses that you pay each year as a percentage of the value of your investment)

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

PORTFOLIO TURNOVER

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 Fund operating expenses or in the Example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 57% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

57.00%

Expense Example [Heading]

rr_ExpenseExampleHeading

EXAMPLE

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Fund's operating expenses remain the same.

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Strategy [Heading]

rr_StrategyHeading

Principal Investment Strategies

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

Under normal circumstances, the International Equity Fund will invest at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in equity securities. Equity securities may include common stocks, preferred stock, warrants, participation notes and depositary receipts. The Fund will invest primarily in equity securities of issuers of all capitalization ranges that are located in at least three countries other than the U.S. It is expected that at least 40% of the Fund's assets will be invested outside the U.S. The Fund will invest primarily in companies located in developed countries, but may also invest in companies located in emerging markets. Generally, the Fund will invest less than 20% of its assets in emerging markets. Emerging market countries are those countries that are: (i) characterized as developing or emerging by any of the World Bank, the United Nations, the International Finance Corporation, or the European Bank for Reconstruction and Development; (ii) included in an emerging markets index by a recognized index provider; or (iii) countries with similar developing or emerging characteristics as countries classified as emerging market countries pursuant to sub-paragraph (i) and (ii) above, in each case determined at the time of purchase.

The Fund uses a multi-manager approach, relying upon a number of sub-advisers (each, a Sub-Adviser and collectively, the Sub-Advisers) with differing investment philosophies to manage portions of the Fund's portfolio under the general supervision of SEI Investments Management Corporation (SIMC), the Fund's adviser.

The Fund may invest in futures contracts, forward contracts and options for hedging purposes, including seeking to manage the Fund's currency exposure to foreign securities and mitigate the Fund's overall risk.

The Fund may purchase futures contracts or shares of exchange-traded funds (ETFs) to gain exposure to a particular portion of the market while awaiting an opportunity to purchase securities or other instruments directly.

Risk [Heading]

rr_RiskHeading

Principal Risks

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

Credit Risk — The risk that the issuer of a security or the counterparty to a contract will default or otherwise become unable to honor a financial obligation.

Currency Risk — As a result of the Fund's investments in securities denominated in, and/or receiving revenues in, foreign currencies, the Fund will be subject to currency risk. Currency risk is the risk that foreign currencies will decline in value relative to the U.S. dollar or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency hedged. In either event, the dollar value of an investment in the Fund would be adversely affected. Currency exchange rates may fluctuate in response to, among other things, changes in interest rates, intervention (or failure to intervene) by U.S. or foreign governments, central banks or supranational entities, or by the imposition of currency controls or other political developments in the United States or abroad.

Depositary Receipts Risk — Depositary receipts, such as American Depositary Receipts (ADRs), are certificates evidencing ownership of shares of a foreign issuer that are issued by depositary banks and generally trade on an established market. Depositary receipts are subject to many of the risks associated with investing directly in foreign securities, including, among other things, political, social and economic developments abroad, currency movements and different legal, regulatory and tax environments.

Derivatives Risk — The Fund's use of futures contracts, forward contracts and options is subject to market risk, leverage risk, correlation risk and liquidity risk. Leverage risk, liquidity risk and market risk are described below. Many over-the-counter (OTC) derivative instruments will not have liquidity beyond the counterparty to the instrument. Correlation risk is the risk that changes in the value of the derivative may not correlate perfectly with the underlying asset, rate or index. The Fund's use of forward contracts is also subject to credit risk and valuation risk. Valuation risk is the risk that the derivative may be difficult to value and/or valued incorrectly. Credit risk is described above. Each of the above risks could cause the Fund to lose more than the principal amount invested in a derivative instrument. Some derivatives have the potential for unlimited loss, regardless of the size of the Fund's initial investment. The other parties to certain derivative contracts present the same types of credit risk as issuers of fixed income securities. The Fund's use of derivatives may also increase the amount of taxes payable by shareholders. Both U.S. and non-U.S. regulators are in the process of adopting and implementing regulations governing derivatives markets, the ultimate impact of which remains unclear.

Equity Market Risk — The risk that stock prices will fall over short or extended periods of time.

Exchange-Traded Funds (ETFs) Risk — The risks of owning shares of an ETF generally reflect the risks of owning the underlying securities the ETF is designed to track, although lack of liquidity in an ETF could result in its value being more volatile than the underlying portfolio securities. When the Fund invests in an ETF, in addition to directly bearing the expenses associated with its own operations, it will bear a pro rata portion of the ETF's expenses.

Foreign Investment/Emerging Markets Risk — The risk that non-U.S. securities may be subject to additional risks due to, among other things, political, social and economic developments abroad, currency movements and different legal, regulatory and tax environments. These additional risks may be heightened with respect to emerging market countries because political turmoil and rapid changes in economic conditions are more likely to occur in these countries.

Investment Style Risk — The risk that developed international equity securities may underperform other segments of the equity markets or the equity markets as a whole.

Leverage Risk — The Fund's use of derivatives may result in the Fund's total investment exposure substantially exceeding the value of its portfolio securities and the Fund's investment returns depending substantially on the performance of securities that the Fund may not directly own. The use of leverage can amplify the effects of market volatility on the Fund's share price and may also cause the Fund to liquidate portfolio positions when it would not be advantageous to do so in order to satisfy its obligations. The Fund's use of leverage may result in a heightened risk of investment loss.

Liquidity Risk — The risk that certain securities may be difficult or impossible to sell at the time and the price that the Fund would like. The Fund may have to lower the price of the security, sell other securities instead or forego an investment opportunity, any of which could have a negative effect on Fund management or performance.

Market Risk — The risk that the market value of a security may move up and down, sometimes rapidly and unpredictably. Market risk may affect a single issuer, an industry, a sector or the equity or bond market as a whole.

Participation Notes (P-Notes) Risk — P-Notes are participation interest notes that are issued by banks or broker-dealers and are designed to offer a return linked to a particular underlying equity, debt, currency or market. Investments in P-Notes involve the same risks associated with a direct investment in the underlying foreign companies or foreign securities markets that they seek to replicate. However, there can be no assurance that the trading price of P-Notes will equal the underlying value of the foreign companies or foreign securities markets that they seek to replicate.

Small and Medium Capitalization Risk — The risk that small and medium capitalization companies in which the Fund may invest may be more vulnerable to adverse business or economic events than larger, more established companies. In particular, small and medium capitalization companies may have limited product lines, markets and financial resources and may depend upon a relatively small management group. Therefore, small capitalization and medium capitalization stocks may be more volatile than those of larger companies. Small capitalization and medium capitalization stocks may be traded OTC or listed on an exchange.

Warrants Risk — Warrants are instruments that entitle the holder to buy an equity security at a specific price for a specific period of time. Warrants may be more speculative than other types of investments. The price of a warrant may be more volatile than the price of its underlying security, and a warrant may offer greater potential for capital appreciation as well as capital loss. A warrant ceases to have value if it is not exercised prior to its expiration date.

Investing in the Fund involves risk, and there is no guarantee that the Fund will achieve its investment goal. You could lose money on your investment in the Fund, just as you could with other investments. 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.

Risk Lose Money [Text]

rr_RiskLoseMoney

Investing in the Fund involves risk, and there is no guarantee that the Fund will achieve its investment goal. You could lose money on your investment in the Fund, just as you could with other investments.

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

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.

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

Performance Information

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The bar chart and the performance table below provide some indication of the risks of investing in the Fund by showing changes in the Fund's performance from year to year for the past ten calendar years and by showing how the Fund's average annual returns for 1, 5 and 10 years, and since the Fund's inception, compare with those of a broad measure of market performance. The performance information shown is based on full calendar years. The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future. For current performance information, please call 1-800-DIAL-SEI.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

The bar chart and the performance table below provide some indication of the risks of investing in the Fund by showing changes in the Fund's performance from year to year for the past ten calendar years and by showing how the Fund's average annual returns for 1, 5 and 10 years, and since the Fund's inception, compare with those of a broad measure of market performance.

Performance Availability Phone [Text]

rr_PerformanceAvailabilityPhone

1-800-DIAL-SEI

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future.

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

Best Quarter: 22.98% (06/30/09)
Worst Quarter: -26.13% (09/30/08)

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Best Quarter:

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Jun. 30, 2009

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

22.98%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Worst Quarter:

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Sep. 30, 2008

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(26.13%)

Performance Table Heading

rr_PerformanceTableHeading

Average Annual Total Returns (for the periods ended December 31, 2017)

Index No Deduction for Fees, Expenses, Taxes [Text]

rr_IndexNoDeductionForFeesExpensesTaxes

(reflects no deduction for fees, expenses or taxes)

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes.

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

Your actual after-tax returns will depend on your tax situation and may differ from those shown. After-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts.

Performance Table Narrative

rr_PerformanceTableNarrativeTextBlock

After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Your actual after-tax returns will depend on your tax situation and may differ from those shown. After-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts.

Class F Prospectus | SIT INTERNATIONAL EQUITY FUND | MSCI EAFE Index Return (reflects no deduction for fees, expenses or taxes)

Risk/Return:

rr_RiskReturnAbstract

Label

rr_AverageAnnualReturnLabel

MSCI EAFE Index Return (reflects no deduction for fees, expenses or taxes)

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

25.03%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

7.90%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

1.94%

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

4.68%

^[1]

Average Annual Returns, Inception Date

rr_AverageAnnualReturnInceptionDate

Dec. 31, 1989

Class F Prospectus | SIT INTERNATIONAL EQUITY FUND | SIT INTERNATIONAL EQUITY FUND - CLASS F, effective 1-31-2017 (formerly Class A)

Risk/Return:

rr_RiskReturnAbstract

Management Fees

rr_ManagementFeesOverAssets

0.51%

Distribution (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

none

Other Expenses

rr_OtherExpensesOverAssets

0.64%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

1.15%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

$ 117

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

365

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

633

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

$ 1,398

Annual Return 2008

rr_AnnualReturn2008

(50.39%)

Annual Return 2009

rr_AnnualReturn2009

24.00%

Annual Return 2010

rr_AnnualReturn2010

10.74%

Annual Return 2011

rr_AnnualReturn2011

(13.52%)

Annual Return 2012

rr_AnnualReturn2012

16.07%

Annual Return 2013

rr_AnnualReturn2013

21.38%

Annual Return 2014

rr_AnnualReturn2014

(6.07%)

Annual Return 2015

rr_AnnualReturn2015

1.86%

Annual Return 2016

rr_AnnualReturn2016

(0.53%)

Annual Return 2017

rr_AnnualReturn2017

26.66%

Label

rr_AverageAnnualReturnLabel

Return Before Taxes

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

26.66%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

7.91%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

none

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

3.90%

Average Annual Returns, Inception Date

rr_AverageAnnualReturnInceptionDate

Dec. 20, 1989

Class F Prospectus | SIT INTERNATIONAL EQUITY FUND | SIT INTERNATIONAL EQUITY FUND - CLASS F, effective 1-31-2017 (formerly Class A) | After Taxes on Distributions

Risk/Return:

rr_RiskReturnAbstract

Label

rr_AverageAnnualReturnLabel

Return After Taxes on Distributions

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

25.95%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

7.54%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

(0.21%)

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

3.12%

Class F Prospectus | SIT INTERNATIONAL EQUITY FUND | SIT INTERNATIONAL EQUITY FUND - CLASS F, effective 1-31-2017 (formerly Class A) | After Taxes on Distributions and Sale of Fund Shares

Risk/Return:

rr_RiskReturnAbstract

Label

rr_AverageAnnualReturnLabel

Return After Taxes on Distributions and Sale of Fund Shares

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

15.08%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

6.16%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

0.03%

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

3.03%

[1] Index returns are shown from December 31, 1989.

XML

Class F Prospectus | SIT EMERGING MARKETS EQUITY FUND

SIT EMERGING MARKETS EQUITY FUND

Investment Goal

Capital appreciation.

Fees and Expenses

The following tables describe the fees and expenses that you may pay if you buy and hold Fund shares.

ANNUAL FUND OPERATING EXPENSES (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses	Class F Prospectus SIT EMERGING MARKETS EQUITY FUND SIT EMERGING MARKETS EQUITY FUND - CLASS F, effective 1-31-2017 (formerly Class A)
Management Fees	1.05%
Distribution (12b-1) Fees	none
Other Expenses	0.77%
Total Annual Fund Operating Expenses	1.82%
Fee Waivers and Expense Reimbursements	(0.10%)
Total Annual Fund Operating Expenses Less Fee Waivers and Expense Reimbursements	1.72%	[1]

EXAMPLE

This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Fund's operating expenses remain the same.

Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Expense Example	1 Year	3 Years	5 Years	10 Years
Class F Prospectus | SIT EMERGING MARKETS EQUITY FUND | SIT EMERGING MARKETS EQUITY FUND - CLASS F, effective 1-31-2017 (formerly Class A) | USD ($)	175	563	976	2,129

PORTFOLIO TURNOVER

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 Fund operating expenses or in the Example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 66% of the average value of its portfolio.

Principal Investment Strategies

Under normal circumstances, the Emerging Markets Equity Fund will invest at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in equity securities of emerging market issuers. Equity securities may include common stocks, preferred stock, warrants, participation notes and depositary receipts. The Fund normally maintains investments in at least six emerging market countries and does not invest more than 35% of its total assets in any one emerging market country. Emerging market countries are those countries that are: (i) characterized as developing or emerging by any of the World Bank, the United Nations, the International Finance Corporation, or the European Bank for Reconstruction and Development; (ii) included in an emerging markets index by a recognized index provider; or (iii) countries with similar developing or emerging characteristics as countries classified as emerging market countries pursuant to sub-paragraph (i) and (ii) above, in each case determined at the time of purchase.

The Fund uses a multi-manager approach, relying upon a number of sub-advisers (each, a Sub-Adviser and collectively, the Sub-Advisers) with differing investment philosophies to manage portions of the Fund's portfolio under the general supervision of SEI Investments Management Corporation (SIMC), the Fund's adviser.

The Fund may invest in swaps based on a single security or an index of securities, futures contracts, forward contracts and options to synthetically obtain exposure to securities or baskets of securities or for hedging purposes, including seeking to manage the Fund's currency exposure to foreign securities and mitigate the Fund's overall risk. Swaps may be used to obtain exposure to different foreign equity markets.

The Fund may purchase futures contracts or shares of exchange-traded funds (ETFs) to gain exposure to a particular portion of the market while awaiting an opportunity to purchase securities or other instruments directly. The Fund may also invest a portion of its assets in securities of companies located in developed foreign countries and securities of small capitalization companies.

Principal Risks

Credit Risk — The risk that the issuer of a security or the counterparty to a contract will default or otherwise become unable to honor a financial obligation.

Currency Risk — As a result of the Fund's investments in securities denominated in, and/or receiving revenues in, foreign currencies, the Fund will be subject to currency risk. Currency risk is the risk that foreign currencies will decline in value relative to the U.S. dollar or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency hedged. In either event, the dollar value of an investment in the Fund would be adversely affected. Currency exchange rates may fluctuate in response to, among other things, changes in interest rates, intervention (or failure to intervene) by U.S. or foreign governments, central banks or supranational entities, or by the imposition of currency controls or other political developments in the United States or abroad.

Depositary Receipts Risk — Depositary receipts, such as American Depositary Receipts (ADRs), are certificates evidencing ownership of shares of a foreign issuer that are issued by depositary banks and generally trade on an established market. Depositary receipts are subject to many of the risks associated with investing directly in foreign securities, including, among other things, political, social and economic developments abroad, currency movements and different legal, regulatory and tax environments.

Derivatives Risk — The Fund's use of futures contracts, forward contracts, options and swaps is subject to market risk, leverage risk, correlation risk and liquidity risk. Leverage risk, liquidity risk and market risk are described below. Many over-the-counter (OTC) derivative instruments will not have liquidity beyond the counterparty to the instrument. Correlation risk is the risk that changes in the value of the derivative may not correlate perfectly with the underlying asset, rate or index. The Fund's use of forward contracts and swap agreements is also subject to credit risk and valuation risk. Valuation risk is the risk that the derivative may be difficult to value and/or valued incorrectly. Credit risk is described above. Each of the above risks could cause the Fund to lose more than the principal amount invested in a derivative instrument. Some derivatives have the potential for unlimited loss, regardless of the size of the Fund's initial investment. The other parties to certain derivative contracts present the same types of credit risk as issuers of fixed income securities. The Fund's use of derivatives may also increase the amount of taxes payable by shareholders. Both U.S. and non-U.S. regulators are in the process of adopting and implementing regulations governing derivatives markets, the ultimate impact of which remains unclear.

Equity Market Risk — The risk that stock prices will fall over short or extended periods of time.

Exchange-Traded Funds (ETFs) Risk — The risks of owning shares of an ETF generally reflect the risks of owning the underlying securities the ETF is designed to track, although lack of liquidity in an ETF could result in its value being more volatile than the underlying portfolio securities. When the Fund invests in an ETF, in addition to directly bearing the expenses associated with its own operations, it will bear a pro rata portion of the ETF's expenses.

Foreign Investment/Emerging Markets Risk — The risk that non-U.S. securities may be subject to additional risks due to, among other things, political, social and economic developments abroad, currency movements and different legal, regulatory and tax environments. These additional risks may be heightened with respect to emerging market countries because political turmoil and rapid changes in economic conditions are more likely to occur in these countries.

Investment Style Risk — The risk that emerging market equity securities may underperform other segments of the equity markets or the equity markets as a whole.

Leverage Risk — The Fund's use of derivatives may result in the Fund's total investment exposure substantially exceeding the value of its portfolio securities and the Fund's investment returns depending substantially on the performance of securities that the Fund may not directly own. The use of leverage can amplify the effects of market volatility on the Fund's share price and may also cause the Fund to liquidate portfolio positions when it would not be advantageous to do so in order to satisfy its obligations. The Fund's use of leverage may result in a heightened risk of investment loss.

Liquidity Risk — The risk that certain securities may be difficult or impossible to sell at the time and the price that the Fund would like. The Fund may have to lower the price of the security, sell other securities instead or forego an investment opportunity, any of which could have a negative effect on Fund management or performance.

Market Risk — The risk that the market value of a security may move up and down, sometimes rapidly and unpredictably. Market risk may affect a single issuer, an industry, a sector or the equity or bond market as a whole.

Participation Notes (P-Notes) Risk — P-Notes are participation interest notes that are issued by banks or broker-dealers and are designed to offer a return linked to a particular underlying equity, debt, currency or market. Investments in P-Notes involve the same risks associated with a direct investment in the underlying foreign companies or foreign securities markets that they seek to replicate. However, there can be no assurance that the trading price of P-Notes will equal the underlying value of the foreign companies or foreign securities markets that they seek to replicate.

Small and Medium Capitalization Risk — The risk that small and medium capitalization companies in which the Fund may invest may be more vulnerable to adverse business or economic events than larger, more established companies. In particular, small and medium capitalization companies may have limited product lines, markets and financial resources and may depend upon a relatively small management group. Therefore, small capitalization and medium capitalization stocks may be more volatile than those of larger companies. Small capitalization and medium capitalization stocks may be traded over the counter or listed on an exchange.

Warrants Risk — Warrants are instruments that entitle the holder to buy an equity security at a specific price for a specific period of time. Warrants may be more speculative than other types of investments. The price of a warrant may be more volatile than the price of its underlying security, and a warrant may offer greater potential for capital appreciation as well as capital loss. A warrant ceases to have value if it is not exercised prior to its expiration date.

Investing in the Fund involves risk, and there is no guarantee that the Fund will achieve its investment goal. You could lose money on your investment in the Fund, just as you could with other investments. 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.

Performance Information

The bar chart and the performance table below provide some indication of the risks of investing in the Fund by showing changes in the Fund's performance from year to year for the past ten calendar years and by showing how the Fund's average annual returns for 1, 5 and 10 years, and since the Fund's inception, compare with those of a broad measure of market performance. The performance information shown is based on full calendar years. The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future. For current performance information, please call 1-800-DIAL-SEI.

Best Quarter: 34.40% (06/30/09)
Worst Quarter: -27.79% (12/31/08)

Average Annual Total Returns (for the periods ended December 31, 2017)

After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Your actual after-tax returns will depend on your tax situation and may differ from those shown. After-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts.

Average Annual Returns - Class F Prospectus - SIT EMERGING MARKETS EQUITY FUND	Label	Average Annual Returns, 1 Year	Average Annual Returns, 5 Years	Average Annual Returns, 10 Years	Average Annual Returns, Since Inception		Average Annual Returns, Inception Date
SIT EMERGING MARKETS EQUITY FUND - CLASS F, effective 1-31-2017 (formerly Class A)	Return Before Taxes	37.27%	4.56%	0.91%	5.11%		Jan. 17, 1995
After Taxes on Distributions | SIT EMERGING MARKETS EQUITY FUND - CLASS F, effective 1-31-2017 (formerly Class A)	Return After Taxes on Distributions	36.52%	4.45%	0.52%	4.61%
After Taxes on Distributions and Sale of Fund Shares | SIT EMERGING MARKETS EQUITY FUND - CLASS F, effective 1-31-2017 (formerly Class A)	Return After Taxes on Distributions and Sale of Fund Shares	21.09%	3.62%	0.75%	4.41%
MSCI Emerging Markets Index Return (reflects no deduction for fees, expenses or taxes)	MSCI Emerging Markets Index Return (reflects no deduction for fees, expenses or taxes)	37.75%	4.73%	2.02%	7.00%	[1]	Jan. 31, 1995

[1] Renewed as of January 31, 2018, SIMC, the Fund's investment adviser, has contractually agreed to waive its management fee as necessary to keep the management fee paid by the Fund during its fiscal year from exceeding 0.95%. This fee waiver agreement shall remain in effect until January 31, 2019 and, unless earlier terminated, shall be automatically renewed for successive one-year periods thereafter. The agreement may be amended or terminated only with the consent of the Board of Trustees.

[1] Index returns are shown from January 31, 1995.

XML

Label

Element

Value

Class F Prospectus | SIT EMERGING MARKETS EQUITY FUND

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

SIT EMERGING MARKETS EQUITY FUND

Objective [Heading]

rr_ObjectiveHeading

Investment Goal

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

Capital appreciation.

Expense [Heading]

rr_ExpenseHeading

Fees and Expenses

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

The following tables describe the fees and expenses that you may pay if you buy and hold Fund shares.

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

ANNUAL FUND OPERATING EXPENSES (expenses that you pay each year as a percentage of the value of your investment)

Fee Waiver or Reimbursement over Assets, Date of Termination

rr_FeeWaiverOrReimbursementOverAssetsDateOfTermination

Jan. 31, 2019

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

PORTFOLIO TURNOVER

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 Fund operating expenses or in the Example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 66% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

66.00%

Expense Example [Heading]

rr_ExpenseExampleHeading

EXAMPLE

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Fund's operating expenses remain the same.

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Strategy [Heading]

rr_StrategyHeading

Principal Investment Strategies

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

Under normal circumstances, the Emerging Markets Equity Fund will invest at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in equity securities of emerging market issuers. Equity securities may include common stocks, preferred stock, warrants, participation notes and depositary receipts. The Fund normally maintains investments in at least six emerging market countries and does not invest more than 35% of its total assets in any one emerging market country. Emerging market countries are those countries that are: (i) characterized as developing or emerging by any of the World Bank, the United Nations, the International Finance Corporation, or the European Bank for Reconstruction and Development; (ii) included in an emerging markets index by a recognized index provider; or (iii) countries with similar developing or emerging characteristics as countries classified as emerging market countries pursuant to sub-paragraph (i) and (ii) above, in each case determined at the time of purchase.

The Fund uses a multi-manager approach, relying upon a number of sub-advisers (each, a Sub-Adviser and collectively, the Sub-Advisers) with differing investment philosophies to manage portions of the Fund's portfolio under the general supervision of SEI Investments Management Corporation (SIMC), the Fund's adviser.

The Fund may invest in swaps based on a single security or an index of securities, futures contracts, forward contracts and options to synthetically obtain exposure to securities or baskets of securities or for hedging purposes, including seeking to manage the Fund's currency exposure to foreign securities and mitigate the Fund's overall risk. Swaps may be used to obtain exposure to different foreign equity markets.

The Fund may purchase futures contracts or shares of exchange-traded funds (ETFs) to gain exposure to a particular portion of the market while awaiting an opportunity to purchase securities or other instruments directly. The Fund may also invest a portion of its assets in securities of companies located in developed foreign countries and securities of small capitalization companies.

Risk [Heading]

rr_RiskHeading

Principal Risks

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

Credit Risk — The risk that the issuer of a security or the counterparty to a contract will default or otherwise become unable to honor a financial obligation.

Currency Risk — As a result of the Fund's investments in securities denominated in, and/or receiving revenues in, foreign currencies, the Fund will be subject to currency risk. Currency risk is the risk that foreign currencies will decline in value relative to the U.S. dollar or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency hedged. In either event, the dollar value of an investment in the Fund would be adversely affected. Currency exchange rates may fluctuate in response to, among other things, changes in interest rates, intervention (or failure to intervene) by U.S. or foreign governments, central banks or supranational entities, or by the imposition of currency controls or other political developments in the United States or abroad.

Depositary Receipts Risk — Depositary receipts, such as American Depositary Receipts (ADRs), are certificates evidencing ownership of shares of a foreign issuer that are issued by depositary banks and generally trade on an established market. Depositary receipts are subject to many of the risks associated with investing directly in foreign securities, including, among other things, political, social and economic developments abroad, currency movements and different legal, regulatory and tax environments.

Derivatives Risk — The Fund's use of futures contracts, forward contracts, options and swaps is subject to market risk, leverage risk, correlation risk and liquidity risk. Leverage risk, liquidity risk and market risk are described below. Many over-the-counter (OTC) derivative instruments will not have liquidity beyond the counterparty to the instrument. Correlation risk is the risk that changes in the value of the derivative may not correlate perfectly with the underlying asset, rate or index. The Fund's use of forward contracts and swap agreements is also subject to credit risk and valuation risk. Valuation risk is the risk that the derivative may be difficult to value and/or valued incorrectly. Credit risk is described above. Each of the above risks could cause the Fund to lose more than the principal amount invested in a derivative instrument. Some derivatives have the potential for unlimited loss, regardless of the size of the Fund's initial investment. The other parties to certain derivative contracts present the same types of credit risk as issuers of fixed income securities. The Fund's use of derivatives may also increase the amount of taxes payable by shareholders. Both U.S. and non-U.S. regulators are in the process of adopting and implementing regulations governing derivatives markets, the ultimate impact of which remains unclear.

Equity Market Risk — The risk that stock prices will fall over short or extended periods of time.

Exchange-Traded Funds (ETFs) Risk — The risks of owning shares of an ETF generally reflect the risks of owning the underlying securities the ETF is designed to track, although lack of liquidity in an ETF could result in its value being more volatile than the underlying portfolio securities. When the Fund invests in an ETF, in addition to directly bearing the expenses associated with its own operations, it will bear a pro rata portion of the ETF's expenses.

Foreign Investment/Emerging Markets Risk — The risk that non-U.S. securities may be subject to additional risks due to, among other things, political, social and economic developments abroad, currency movements and different legal, regulatory and tax environments. These additional risks may be heightened with respect to emerging market countries because political turmoil and rapid changes in economic conditions are more likely to occur in these countries.

Investment Style Risk — The risk that emerging market equity securities may underperform other segments of the equity markets or the equity markets as a whole.

Leverage Risk — The Fund's use of derivatives may result in the Fund's total investment exposure substantially exceeding the value of its portfolio securities and the Fund's investment returns depending substantially on the performance of securities that the Fund may not directly own. The use of leverage can amplify the effects of market volatility on the Fund's share price and may also cause the Fund to liquidate portfolio positions when it would not be advantageous to do so in order to satisfy its obligations. The Fund's use of leverage may result in a heightened risk of investment loss.

Liquidity Risk — The risk that certain securities may be difficult or impossible to sell at the time and the price that the Fund would like. The Fund may have to lower the price of the security, sell other securities instead or forego an investment opportunity, any of which could have a negative effect on Fund management or performance.

Market Risk — The risk that the market value of a security may move up and down, sometimes rapidly and unpredictably. Market risk may affect a single issuer, an industry, a sector or the equity or bond market as a whole.

Participation Notes (P-Notes) Risk — P-Notes are participation interest notes that are issued by banks or broker-dealers and are designed to offer a return linked to a particular underlying equity, debt, currency or market. Investments in P-Notes involve the same risks associated with a direct investment in the underlying foreign companies or foreign securities markets that they seek to replicate. However, there can be no assurance that the trading price of P-Notes will equal the underlying value of the foreign companies or foreign securities markets that they seek to replicate.

Small and Medium Capitalization Risk — The risk that small and medium capitalization companies in which the Fund may invest may be more vulnerable to adverse business or economic events than larger, more established companies. In particular, small and medium capitalization companies may have limited product lines, markets and financial resources and may depend upon a relatively small management group. Therefore, small capitalization and medium capitalization stocks may be more volatile than those of larger companies. Small capitalization and medium capitalization stocks may be traded over the counter or listed on an exchange.

Warrants Risk — Warrants are instruments that entitle the holder to buy an equity security at a specific price for a specific period of time. Warrants may be more speculative than other types of investments. The price of a warrant may be more volatile than the price of its underlying security, and a warrant may offer greater potential for capital appreciation as well as capital loss. A warrant ceases to have value if it is not exercised prior to its expiration date.

Investing in the Fund involves risk, and there is no guarantee that the Fund will achieve its investment goal. You could lose money on your investment in the Fund, just as you could with other investments. 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.

Risk Lose Money [Text]

rr_RiskLoseMoney

Investing in the Fund involves risk, and there is no guarantee that the Fund will achieve its investment goal. You could lose money on your investment in the Fund, just as you could with other investments.

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

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.

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

Performance Information

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The bar chart and the performance table below provide some indication of the risks of investing in the Fund by showing changes in the Fund's performance from year to year for the past ten calendar years and by showing how the Fund's average annual returns for 1, 5 and 10 years, and since the Fund's inception, compare with those of a broad measure of market performance. The performance information shown is based on full calendar years. The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future. For current performance information, please call 1-800-DIAL-SEI.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

The bar chart and the performance table below provide some indication of the risks of investing in the Fund by showing changes in the Fund's performance from year to year for the past ten calendar years and by showing how the Fund's average annual returns for 1, 5 and 10 years, and since the Fund's inception, compare with those of a broad measure of market performance.

Performance Availability Phone [Text]

rr_PerformanceAvailabilityPhone

1-800-DIAL-SEI

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future.

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

Best Quarter: 34.40% (06/30/09)
Worst Quarter: -27.79% (12/31/08)

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Best Quarter:

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Jun. 30, 2009

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

34.40%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Worst Quarter:

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Dec. 31, 2008

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(27.79%)

Performance Table Heading

rr_PerformanceTableHeading

Average Annual Total Returns (for the periods ended December 31, 2017)

Index No Deduction for Fees, Expenses, Taxes [Text]

rr_IndexNoDeductionForFeesExpensesTaxes

(reflects no deduction for fees, expenses or taxes)

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes.

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

Your actual after-tax returns will depend on your tax situation and may differ from those shown. After-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts.

Performance Table Narrative

rr_PerformanceTableNarrativeTextBlock

After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Your actual after-tax returns will depend on your tax situation and may differ from those shown. After-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts.

Class F Prospectus | SIT EMERGING MARKETS EQUITY FUND | MSCI Emerging Markets Index Return (reflects no deduction for fees, expenses or taxes)

Risk/Return:

rr_RiskReturnAbstract

Label

rr_AverageAnnualReturnLabel

MSCI Emerging Markets Index Return (reflects no deduction for fees, expenses or taxes)

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

37.75%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

4.73%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

2.02%

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

7.00%

^[1]

Average Annual Returns, Inception Date

rr_AverageAnnualReturnInceptionDate

Jan. 31, 1995

Class F Prospectus | SIT EMERGING MARKETS EQUITY FUND | SIT EMERGING MARKETS EQUITY FUND - CLASS F, effective 1-31-2017 (formerly Class A)

Risk/Return:

rr_RiskReturnAbstract

Management Fees

rr_ManagementFeesOverAssets

1.05%

Distribution (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

none

Other Expenses

rr_OtherExpensesOverAssets

0.77%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

1.82%

Fee Waivers and Expense Reimbursements

rr_FeeWaiverOrReimbursementOverAssets

(0.10%)

Total Annual Fund Operating Expenses Less Fee Waivers and Expense Reimbursements

rr_NetExpensesOverAssets

1.72%

^[2]

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

$ 175

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

563

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

976

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

$ 2,129

Annual Return 2008

rr_AnnualReturn2008

(52.68%)

Annual Return 2009

rr_AnnualReturn2009

75.07%

Annual Return 2010

rr_AnnualReturn2010

17.70%

Annual Return 2011

rr_AnnualReturn2011

(23.32%)

Annual Return 2012

rr_AnnualReturn2012

17.10%

Annual Return 2013

rr_AnnualReturn2013

(0.26%)

Annual Return 2014

rr_AnnualReturn2014

(5.10%)

Annual Return 2015

rr_AnnualReturn2015

(14.49%)

Annual Return 2016

rr_AnnualReturn2016

12.49%

Annual Return 2017

rr_AnnualReturn2017

37.27%

Label

rr_AverageAnnualReturnLabel

Return Before Taxes

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

37.27%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

4.56%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

0.91%

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

5.11%

Average Annual Returns, Inception Date

rr_AverageAnnualReturnInceptionDate

Jan. 17, 1995

Class F Prospectus | SIT EMERGING MARKETS EQUITY FUND | SIT EMERGING MARKETS EQUITY FUND - CLASS F, effective 1-31-2017 (formerly Class A) | After Taxes on Distributions

Risk/Return:

rr_RiskReturnAbstract

Label

rr_AverageAnnualReturnLabel

Return After Taxes on Distributions

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

36.52%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

4.45%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

0.52%

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

4.61%

Class F Prospectus | SIT EMERGING MARKETS EQUITY FUND | SIT EMERGING MARKETS EQUITY FUND - CLASS F, effective 1-31-2017 (formerly Class A) | After Taxes on Distributions and Sale of Fund Shares

Risk/Return:

rr_RiskReturnAbstract

Label

rr_AverageAnnualReturnLabel

Return After Taxes on Distributions and Sale of Fund Shares

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

21.09%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

3.62%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

0.75%

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

4.41%

[1] Index returns are shown from January 31, 1995.

[2] Renewed as of January 31, 2018, SIMC, the Fund's investment adviser, has contractually agreed to waive its management fee as necessary to keep the management fee paid by the Fund during its fiscal year from exceeding 0.95%. This fee waiver agreement shall remain in effect until January 31, 2019 and, unless earlier terminated, shall be automatically renewed for successive one-year periods thereafter. The agreement may be amended or terminated only with the consent of the Board of Trustees.

XML

Class F Prospectus | SIT INTERNATIONAL FIXED INCOME FUND

SIT INTERNATIONAL FIXED INCOME FUND

Investment Goal

Capital appreciation and current income.

Fees and Expenses

The following tables describe the fees and expenses that you may pay if you buy and hold Fund shares.

ANNUAL FUND OPERATING EXPENSES (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses	Class F Prospectus SIT INTERNATIONAL FIXED INCOME FUND SIT INTERNATIONAL FIXED INCOME FUND - CLASS F, effective 1-31-2017 (formerly Class A)
Management Fees	0.30%
Distribution (12b-1) Fees	none
Other Expenses	0.78%
Total Annual Fund Operating Expenses	1.08%

EXAMPLE

This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Fund's operating expenses remain the same.

Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Expense Example	1 Year	3 Years	5 Years	10 Years
Class F Prospectus | SIT INTERNATIONAL FIXED INCOME FUND | SIT INTERNATIONAL FIXED INCOME FUND - CLASS F, effective 1-31-2017 (formerly Class A) | USD ($)	110	343	595	1,317

PORTFOLIO TURNOVER

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 Fund operating expenses or in the Example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 113% of the average value of its portfolio.

Principal Investment Strategies

Under normal circumstances, the International Fixed Income Fund will invest at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in fixed income securities. The Fund will invest primarily in investment grade foreign government and corporate fixed income securities, as well as foreign mortgage-backed and/or asset-backed fixed income securities, of issuers located in at least three countries other than the U.S. (including, to a lesser extent, emerging market countries). It is expected that at least 40% of the Fund's assets will be invested in non-U.S. securities. Other fixed income securities in which the Fund may invest include: (i) securities issued or guaranteed by the U.S. Government and its agencies and instrumentalities and obligations of U.S. commercial banks, such as certificates of deposit, time deposits, bankers' acceptances and bank notes; (ii) U.S. corporate debt securities and mortgage-backed and asset-backed securities; and (iii) obligations of supranational entities.

The Fund uses a multi-manager approach, relying upon a number of sub-advisers (each, a Sub-Adviser and collectively, the Sub-Advisers) with differing investment philosophies to manage portions of the Fund's portfolio under the general supervision of SEI Investments Management Corporation (SIMC), the Fund's adviser. In selecting investments for the Fund, the Sub-Advisers choose securities issued by corporations and governments located in various countries, looking for opportunities to achieve capital appreciation and gain, as well as current income. There are no restrictions on the Fund's average portfolio maturity or on the maturity of any specific security.

The Sub-Advisers may seek to enhance the Fund's return by actively managing the Fund's foreign currency exposure. In managing the Fund's currency exposure, the Sub-Advisers buy and sell currencies (i.e., take long or short positions) using derivatives, principally futures, foreign currency forward contracts and currency swaps. The Fund may take long and short positions in foreign currencies in excess of the value of the Fund's assets denominated in a particular currency or when the Fund does not own assets denominated in that currency. The Fund may also engage in currency transactions in an attempt to take advantage of certain inefficiencies in the currency exchange market, to increase its exposure to a foreign currency or to shift exposure to foreign currency fluctuations from one currency to another. In managing the Fund's currency exposure from foreign securities, the Sub-Advisers may buy and sell currencies for hedging or for speculative purposes.

The Fund may also invest in futures contracts, forward contracts and swaps for speculative or hedging purposes. Futures contracts, forward contracts and swaps are used to synthetically obtain exposure to the securities identified above or baskets of such securities and to manage the Fund's interest rate duration and yield curve exposure. These derivatives are also used to mitigate the Fund's overall level of risk and/or the Fund's risk to particular types of securities, currencies or market segments. Interest rate swaps are further used to manage the Fund's yield spread sensitivity. When the Fund seeks to take an active long or short position with respect to the likelihood of an event of default of a security or basket of securities, the Fund may use credit default swaps. The Fund may buy credit default swaps in an attempt to manage credit risk where the Fund has credit exposure to an issuer and the Fund may sell credit default swaps to more efficiently gain credit exposure to such security or basket of securities.

The Fund will also invest in securities rated below investment grade (junk bonds). However, in general, the Fund will purchase bonds with a rating of CCC or above. The Fund also invests a portion of its assets in bank loans, which are generally non-investment grade floating rate instruments. The Fund may invest in bank loans in the form of participations in the loans or assignments of all or a portion of the loans from third parties.

The Fund may purchase shares of exchange-traded funds (ETFs) to gain exposure to a particular portion of the market while awaiting an opportunity to purchase securities or other instruments directly. Due to its investment strategy, the Fund may buy and sell securities and other instruments frequently.

Principal Risks

Asset-Backed Securities Risk — Payment of principal and interest on asset-backed securities is dependent largely on the cash flows generated by the assets backing the securities. Securitization trusts generally do not have any assets or sources of funds other than the receivables and related property they own, and asset-backed securities are generally not insured or guaranteed by the related sponsor or any other entity. Asset-backed securities may be more illiquid than more conventional types of fixed-income securities that the Fund acquires.

Bank Loans Risk — With respect to bank loans, the Fund will assume the credit risk of both the borrower and the lender that is selling the participation. The Fund may also have difficulty disposing of bank loans because, in certain cases, the market for such instruments is not highly liquid.

Below Investment Grade Securities (Junk Bonds) Risk — Fixed income securities rated below investment grade (junk bonds) involve greater risks of default or downgrade and are generally more volatile than investment grade securities because the prospect for repayment of principal and interest of many of these securities is speculative. Because these securities typically offer a higher rate of return to compensate investors for these risks, they are sometimes referred to as "high yield bonds," but there is no guarantee that an investment in these securities will result in a high rate of return.

Corporate Fixed Income Securities Risk — Corporate fixed income securities respond to economic developments, especially changes in interest rates, as well as perceptions of the creditworthiness and business prospects of individual issuers.

Credit Risk — The risk that the issuer of a security or the counterparty to a contract will default or otherwise become unable to honor a financial obligation.

Currency Risk — As a result of the Fund's investments in securities or other investments denominated in, and/or receiving revenues in, foreign currencies and the Fund's active management of its currency exposures, the Fund will be subject to currency risk. Currency risk is the risk that foreign currencies will decline in value relative to the U.S. dollar or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency hedged. In either event, the dollar value of an investment in the Fund would be adversely affected. Due to the Fund's active positions in currencies, it will be subject to the risk that currency exchange rates may fluctuate in response to, among other things, changes in interest rates, intervention (or failure to intervene) by U.S. or foreign governments, central banks or supranational entities, or by the imposition of currency controls or other political developments in the United States or abroad.

Derivatives Risk — The Fund's use of swaps, futures and forward contracts is subject to market risk, leverage risk, correlation risk and liquidity risk. Leverage risk, liquidity risk and market risk are described below. Many over-the-counter (OTC) derivative instruments will not have liquidity beyond the counterparty to the instrument. Correlation risk is the risk that changes in the value of the derivative may not correlate perfectly with the underlying asset, rate or index. The Fund's use of swaps and forward contracts is also subject to credit risk and valuation risk. Valuation risk is the risk that the derivative may be difficult to value and/or valued incorrectly. Credit risk is described above. Each of the above risks could cause the Fund to lose more than the principal amount invested in a derivative instrument. Some derivatives have the potential for unlimited loss, regardless of the size of the Fund's initial investment. The other parties to certain derivative contracts present the same types of credit risk as issuers of fixed income securities. The Fund's use of derivatives may also increase the amount of taxes payable by shareholders. Both U.S. and non-U.S. regulators are in the process of adopting and implementing regulations governing derivatives markets, the ultimate impact of which remains unclear.

Duration Risk — The longer-term securities in which the Fund may invest tend to be more volatile than shorter-term securities. A portfolio with a longer average portfolio duration is more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration.

Exchange-Traded Funds (ETFs) Risk — The risks of owning shares of an ETF generally reflect the risks of owning the underlying securities the ETF is designed to track, although lack of liquidity in an ETF could result in its value being more volatile than the underlying portfolio securities. When the Fund invests in an ETF, in addition to directly bearing the expenses associated with its own operations, it will bear a pro rata portion of the ETF's expenses.

Extension Risk — The risk that rising interest rates may extend the duration of a fixed income security, typically reducing the security's value.

Fixed Income Market Risk — The prices of the Fund's fixed income securities respond to economic developments, particularly interest rate changes, as well as to perceptions about the creditworthiness of individual issuers, including governments and their agencies. Generally, the Fund's fixed income securities will decrease in value if interest rates rise and vice versa. In a low interest rate environment, risks associated with rising rates are heightened. Declines in dealer market-making capacity as a result of structural or regulatory changes could further decrease liquidity and/or increase volatility in the fixed income markets. In the case of foreign securities, price fluctuations will reflect international economic and political events, as well as changes in currency valuations relative to the U.S. dollar. In response to these events, the Fund's value may fluctuate and/or the Fund may experience increased redemptions from shareholders, which may impact the Fund's liquidity or force the Fund to sell securities into a declining or illiquid market.

Foreign Investment/Emerging Markets Risk — The risk that non-U.S. securities may be subject to additional risks due to, among other things, political, social and economic developments abroad, currency movements and different legal, regulatory and tax environments. These additional risks may be heightened with respect to emerging market countries because political turmoil and rapid changes in economic conditions are more likely to occur in these countries.

Foreign Sovereign Debt Securities Risk — The risks that: (i) the governmental entity that controls the repayment of sovereign debt may not be willing or able to repay the principal and/or interest when it becomes due because of factors such as debt service burden, political constraints, cash flow problems and other national economic factors; (ii) governments may default on their debt securities, which may require holders of such securities to participate in debt rescheduling or additional lending to defaulting governments; and (iii) there is no bankruptcy proceeding by which defaulted sovereign debt may be collected in whole or in part.

Interest Rate Risk — The risk that a rise in interest rates will cause a fall in the value of fixed income securities, including U.S. Government securities, in which the Fund invests. Although U.S. Government securities are considered to be among the safest investments, they are not guaranteed against price movements due to changing interest rates. A low interest rate environment may present greater interest rate risk, because there may be a greater likelihood of rates increasing and rates may increase more rapidly.

Investment Style Risk — The risk that developed international fixed income securities may underperform other segments of the fixed income markets or the fixed income markets as a whole.

Leverage Risk — The Fund's use of derivatives may result in the Fund's total investment exposure substantially exceeding the value of its portfolio securities and the Fund's investment returns depending substantially on the performance of securities that the Fund may not directly own. The use of leverage can amplify the effects of market volatility on the Fund's share price and may also cause the Fund to liquidate portfolio positions when it would not be advantageous to do so in order to satisfy its obligations. The Fund's use of leverage may result in a heightened risk of investment loss.

Liquidity Risk — The risk that certain securities may be difficult or impossible to sell at the time and the price that the Fund would like. The Fund may have to lower the price of the security, sell other securities instead or forego an investment opportunity, any of which could have a negative effect on Fund management or performance.

Market Risk — The risk that the market value of a security may move up and down, sometimes rapidly and unpredictably. Market risk may affect a single issuer, an industry, a sector or the equity or bond market as a whole.

Mortgage-Backed Securities Risk — Mortgage-backed securities are affected significantly by the rate of prepayments and modifications of the mortgage loans backing those securities, as well as by other factors such as borrower defaults, delinquencies, realized or liquidation losses and other shortfalls. Mortgage-backed securities are particularly sensitive to prepayment risk, which is described below, given that the term to maturity for mortgage loans is generally substantially longer than the expected lives of those securities; however, the timing and amount of prepayments cannot be accurately predicted. The timing of changes in the rate of prepayments of the mortgage loans may significantly affect the Fund's actual yield to maturity on any mortgage-backed securities, even if the average rate of principal payments is consistent with the Fund's expectation. Along with prepayment risk, mortgage-backed securities are significantly affected by interest rate risk, which is described above. In a low interest rate environment, mortgage loan prepayments would generally be expected to increase due to factors such as refinancings and loan modifications at lower interest rates. In contrast, if prevailing interest rates rise, prepayments of mortgage loans would generally be expected to decline and therefore extend the weighted average lives of mortgage-backed securities held or acquired by the Fund.

Non-Diversified Risk — The Fund is non-diversified, which means that it may invest in the securities of relatively few issuers. As a result, the Fund may be more susceptible to a single adverse economic or political occurrence affecting one or more of these issuers and may experience increased volatility due to its investments in those securities.

Portfolio Turnover Risk — Due to its investment strategy, the Fund may buy and sell securities frequently. This may result in higher transaction costs and additional capital gains tax liabilities, which may affect the Fund's performance.

Prepayment Risk — The risk that in a declining interest rate environment, fixed income securities with stated interest rates may have the principal paid earlier than expected, requiring the Fund to invest the proceeds at generally lower interest rates.

U.S. Government Securities Risk — Although U.S. Government securities are considered to be among the safest investments, they are not guaranteed against price movements due to changing interest rates. Obligations issued by some U.S. Government agencies are backed by the U.S. Treasury, while others are backed solely by the ability of the agency to borrow from the U.S. Treasury or by the agency's own resources.

Investing in the Fund involves risk, and there is no guarantee that the Fund will achieve its investment goal. You could lose money on your investment in the Fund, just as you could with other investments. 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.

Performance Information

The bar chart and the performance table below provide some indication of the risks of investing in the Fund by showing changes in the Fund's performance from year to year for the past ten calendar years and by showing how the Fund's average annual returns for 1, 5 and 10 years, and since the Fund's inception, compare with those of a broad measure of market performance. The performance information shown is based on full calendar years. The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future. For current performance information, please call 1-800-DIAL-SEI.

Best Quarter: 6.35% (09/30/09)
Worst Quarter: -3.02% (06/30/15)

Average Annual Total Returns (for the periods ended December 31, 2017)

After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Your actual after-tax returns will depend on your tax situation and may differ from those shown. After-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts.

Average Annual Returns - Class F Prospectus - SIT INTERNATIONAL FIXED INCOME FUND	Label	Average Annual Returns, 1 Year	Average Annual Returns, 5 Years	Average Annual Returns, 10 Years	Average Annual Returns, Since Inception		Average Annual Returns, Inception Date
SIT INTERNATIONAL FIXED INCOME FUND - CLASS F, effective 1-31-2017 (formerly Class A)	Return Before Taxes	1.79%	2.87%	3.49%	4.27%		Sep. 01, 1993
After Taxes on Distributions | SIT INTERNATIONAL FIXED INCOME FUND - CLASS F, effective 1-31-2017 (formerly Class A)	Return After Taxes on Distributions	1.79%	1.43%	1.93%	2.71%
After Taxes on Distributions and Sale of Fund Shares | SIT INTERNATIONAL FIXED INCOME FUND - CLASS F, effective 1-31-2017 (formerly Class A)	Return After Taxes on Distributions and Sale of Fund Shares	1.02%	1.53%	2.03%	2.72%
Bloomberg Barclays Global Aggregate ex-US Index, Hedged Return (reflects no deduction for fees, expenses or taxes)	Bloomberg Barclays Global Aggregate ex-US Index, Hedged Return (reflects no deduction for fees, expenses or taxes)	2.48%	3.70%	4.23%	5.65%	[1]	Sep. 30, 1993

[1] Index returns are shown from September 30, 1993.

XML

Label

Element

Value

Class F Prospectus | SIT INTERNATIONAL FIXED INCOME FUND

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

SIT INTERNATIONAL FIXED INCOME FUND

Objective [Heading]

rr_ObjectiveHeading

Investment Goal

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

Capital appreciation and current income.

Expense [Heading]

rr_ExpenseHeading

Fees and Expenses

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

The following tables describe the fees and expenses that you may pay if you buy and hold Fund shares.

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

ANNUAL FUND OPERATING EXPENSES (expenses that you pay each year as a percentage of the value of your investment)

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

PORTFOLIO TURNOVER

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 Fund operating expenses or in the Example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 113% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

113.00%

Expense Example [Heading]

rr_ExpenseExampleHeading

EXAMPLE

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Fund's operating expenses remain the same.

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Strategy [Heading]

rr_StrategyHeading

Principal Investment Strategies

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

Under normal circumstances, the International Fixed Income Fund will invest at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in fixed income securities. The Fund will invest primarily in investment grade foreign government and corporate fixed income securities, as well as foreign mortgage-backed and/or asset-backed fixed income securities, of issuers located in at least three countries other than the U.S. (including, to a lesser extent, emerging market countries). It is expected that at least 40% of the Fund's assets will be invested in non-U.S. securities. Other fixed income securities in which the Fund may invest include: (i) securities issued or guaranteed by the U.S. Government and its agencies and instrumentalities and obligations of U.S. commercial banks, such as certificates of deposit, time deposits, bankers' acceptances and bank notes; (ii) U.S. corporate debt securities and mortgage-backed and asset-backed securities; and (iii) obligations of supranational entities.

The Fund uses a multi-manager approach, relying upon a number of sub-advisers (each, a Sub-Adviser and collectively, the Sub-Advisers) with differing investment philosophies to manage portions of the Fund's portfolio under the general supervision of SEI Investments Management Corporation (SIMC), the Fund's adviser. In selecting investments for the Fund, the Sub-Advisers choose securities issued by corporations and governments located in various countries, looking for opportunities to achieve capital appreciation and gain, as well as current income. There are no restrictions on the Fund's average portfolio maturity or on the maturity of any specific security.

The Sub-Advisers may seek to enhance the Fund's return by actively managing the Fund's foreign currency exposure. In managing the Fund's currency exposure, the Sub-Advisers buy and sell currencies (i.e., take long or short positions) using derivatives, principally futures, foreign currency forward contracts and currency swaps. The Fund may take long and short positions in foreign currencies in excess of the value of the Fund's assets denominated in a particular currency or when the Fund does not own assets denominated in that currency. The Fund may also engage in currency transactions in an attempt to take advantage of certain inefficiencies in the currency exchange market, to increase its exposure to a foreign currency or to shift exposure to foreign currency fluctuations from one currency to another. In managing the Fund's currency exposure from foreign securities, the Sub-Advisers may buy and sell currencies for hedging or for speculative purposes.

The Fund may also invest in futures contracts, forward contracts and swaps for speculative or hedging purposes. Futures contracts, forward contracts and swaps are used to synthetically obtain exposure to the securities identified above or baskets of such securities and to manage the Fund's interest rate duration and yield curve exposure. These derivatives are also used to mitigate the Fund's overall level of risk and/or the Fund's risk to particular types of securities, currencies or market segments. Interest rate swaps are further used to manage the Fund's yield spread sensitivity. When the Fund seeks to take an active long or short position with respect to the likelihood of an event of default of a security or basket of securities, the Fund may use credit default swaps. The Fund may buy credit default swaps in an attempt to manage credit risk where the Fund has credit exposure to an issuer and the Fund may sell credit default swaps to more efficiently gain credit exposure to such security or basket of securities.

The Fund will also invest in securities rated below investment grade (junk bonds). However, in general, the Fund will purchase bonds with a rating of CCC or above. The Fund also invests a portion of its assets in bank loans, which are generally non-investment grade floating rate instruments. The Fund may invest in bank loans in the form of participations in the loans or assignments of all or a portion of the loans from third parties.

The Fund may purchase shares of exchange-traded funds (ETFs) to gain exposure to a particular portion of the market while awaiting an opportunity to purchase securities or other instruments directly. Due to its investment strategy, the Fund may buy and sell securities and other instruments frequently.

Risk [Heading]

rr_RiskHeading

Principal Risks

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

Asset-Backed Securities Risk — Payment of principal and interest on asset-backed securities is dependent largely on the cash flows generated by the assets backing the securities. Securitization trusts generally do not have any assets or sources of funds other than the receivables and related property they own, and asset-backed securities are generally not insured or guaranteed by the related sponsor or any other entity. Asset-backed securities may be more illiquid than more conventional types of fixed-income securities that the Fund acquires.

Bank Loans Risk — With respect to bank loans, the Fund will assume the credit risk of both the borrower and the lender that is selling the participation. The Fund may also have difficulty disposing of bank loans because, in certain cases, the market for such instruments is not highly liquid.

Below Investment Grade Securities (Junk Bonds) Risk — Fixed income securities rated below investment grade (junk bonds) involve greater risks of default or downgrade and are generally more volatile than investment grade securities because the prospect for repayment of principal and interest of many of these securities is speculative. Because these securities typically offer a higher rate of return to compensate investors for these risks, they are sometimes referred to as "high yield bonds," but there is no guarantee that an investment in these securities will result in a high rate of return.

Corporate Fixed Income Securities Risk — Corporate fixed income securities respond to economic developments, especially changes in interest rates, as well as perceptions of the creditworthiness and business prospects of individual issuers.

Credit Risk — The risk that the issuer of a security or the counterparty to a contract will default or otherwise become unable to honor a financial obligation.

Currency Risk — As a result of the Fund's investments in securities or other investments denominated in, and/or receiving revenues in, foreign currencies and the Fund's active management of its currency exposures, the Fund will be subject to currency risk. Currency risk is the risk that foreign currencies will decline in value relative to the U.S. dollar or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency hedged. In either event, the dollar value of an investment in the Fund would be adversely affected. Due to the Fund's active positions in currencies, it will be subject to the risk that currency exchange rates may fluctuate in response to, among other things, changes in interest rates, intervention (or failure to intervene) by U.S. or foreign governments, central banks or supranational entities, or by the imposition of currency controls or other political developments in the United States or abroad.

Derivatives Risk — The Fund's use of swaps, futures and forward contracts is subject to market risk, leverage risk, correlation risk and liquidity risk. Leverage risk, liquidity risk and market risk are described below. Many over-the-counter (OTC) derivative instruments will not have liquidity beyond the counterparty to the instrument. Correlation risk is the risk that changes in the value of the derivative may not correlate perfectly with the underlying asset, rate or index. The Fund's use of swaps and forward contracts is also subject to credit risk and valuation risk. Valuation risk is the risk that the derivative may be difficult to value and/or valued incorrectly. Credit risk is described above. Each of the above risks could cause the Fund to lose more than the principal amount invested in a derivative instrument. Some derivatives have the potential for unlimited loss, regardless of the size of the Fund's initial investment. The other parties to certain derivative contracts present the same types of credit risk as issuers of fixed income securities. The Fund's use of derivatives may also increase the amount of taxes payable by shareholders. Both U.S. and non-U.S. regulators are in the process of adopting and implementing regulations governing derivatives markets, the ultimate impact of which remains unclear.

Duration Risk — The longer-term securities in which the Fund may invest tend to be more volatile than shorter-term securities. A portfolio with a longer average portfolio duration is more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration.

Exchange-Traded Funds (ETFs) Risk — The risks of owning shares of an ETF generally reflect the risks of owning the underlying securities the ETF is designed to track, although lack of liquidity in an ETF could result in its value being more volatile than the underlying portfolio securities. When the Fund invests in an ETF, in addition to directly bearing the expenses associated with its own operations, it will bear a pro rata portion of the ETF's expenses.

Extension Risk — The risk that rising interest rates may extend the duration of a fixed income security, typically reducing the security's value.

Fixed Income Market Risk — The prices of the Fund's fixed income securities respond to economic developments, particularly interest rate changes, as well as to perceptions about the creditworthiness of individual issuers, including governments and their agencies. Generally, the Fund's fixed income securities will decrease in value if interest rates rise and vice versa. In a low interest rate environment, risks associated with rising rates are heightened. Declines in dealer market-making capacity as a result of structural or regulatory changes could further decrease liquidity and/or increase volatility in the fixed income markets. In the case of foreign securities, price fluctuations will reflect international economic and political events, as well as changes in currency valuations relative to the U.S. dollar. In response to these events, the Fund's value may fluctuate and/or the Fund may experience increased redemptions from shareholders, which may impact the Fund's liquidity or force the Fund to sell securities into a declining or illiquid market.

Foreign Investment/Emerging Markets Risk — The risk that non-U.S. securities may be subject to additional risks due to, among other things, political, social and economic developments abroad, currency movements and different legal, regulatory and tax environments. These additional risks may be heightened with respect to emerging market countries because political turmoil and rapid changes in economic conditions are more likely to occur in these countries.

Foreign Sovereign Debt Securities Risk — The risks that: (i) the governmental entity that controls the repayment of sovereign debt may not be willing or able to repay the principal and/or interest when it becomes due because of factors such as debt service burden, political constraints, cash flow problems and other national economic factors; (ii) governments may default on their debt securities, which may require holders of such securities to participate in debt rescheduling or additional lending to defaulting governments; and (iii) there is no bankruptcy proceeding by which defaulted sovereign debt may be collected in whole or in part.

Interest Rate Risk — The risk that a rise in interest rates will cause a fall in the value of fixed income securities, including U.S. Government securities, in which the Fund invests. Although U.S. Government securities are considered to be among the safest investments, they are not guaranteed against price movements due to changing interest rates. A low interest rate environment may present greater interest rate risk, because there may be a greater likelihood of rates increasing and rates may increase more rapidly.

Investment Style Risk — The risk that developed international fixed income securities may underperform other segments of the fixed income markets or the fixed income markets as a whole.

Leverage Risk — The Fund's use of derivatives may result in the Fund's total investment exposure substantially exceeding the value of its portfolio securities and the Fund's investment returns depending substantially on the performance of securities that the Fund may not directly own. The use of leverage can amplify the effects of market volatility on the Fund's share price and may also cause the Fund to liquidate portfolio positions when it would not be advantageous to do so in order to satisfy its obligations. The Fund's use of leverage may result in a heightened risk of investment loss.

Liquidity Risk — The risk that certain securities may be difficult or impossible to sell at the time and the price that the Fund would like. The Fund may have to lower the price of the security, sell other securities instead or forego an investment opportunity, any of which could have a negative effect on Fund management or performance.

Market Risk — The risk that the market value of a security may move up and down, sometimes rapidly and unpredictably. Market risk may affect a single issuer, an industry, a sector or the equity or bond market as a whole.

Mortgage-Backed Securities Risk — Mortgage-backed securities are affected significantly by the rate of prepayments and modifications of the mortgage loans backing those securities, as well as by other factors such as borrower defaults, delinquencies, realized or liquidation losses and other shortfalls. Mortgage-backed securities are particularly sensitive to prepayment risk, which is described below, given that the term to maturity for mortgage loans is generally substantially longer than the expected lives of those securities; however, the timing and amount of prepayments cannot be accurately predicted. The timing of changes in the rate of prepayments of the mortgage loans may significantly affect the Fund's actual yield to maturity on any mortgage-backed securities, even if the average rate of principal payments is consistent with the Fund's expectation. Along with prepayment risk, mortgage-backed securities are significantly affected by interest rate risk, which is described above. In a low interest rate environment, mortgage loan prepayments would generally be expected to increase due to factors such as refinancings and loan modifications at lower interest rates. In contrast, if prevailing interest rates rise, prepayments of mortgage loans would generally be expected to decline and therefore extend the weighted average lives of mortgage-backed securities held or acquired by the Fund.

Non-Diversified Risk — The Fund is non-diversified, which means that it may invest in the securities of relatively few issuers. As a result, the Fund may be more susceptible to a single adverse economic or political occurrence affecting one or more of these issuers and may experience increased volatility due to its investments in those securities.

Portfolio Turnover Risk — Due to its investment strategy, the Fund may buy and sell securities frequently. This may result in higher transaction costs and additional capital gains tax liabilities, which may affect the Fund's performance.

Prepayment Risk — The risk that in a declining interest rate environment, fixed income securities with stated interest rates may have the principal paid earlier than expected, requiring the Fund to invest the proceeds at generally lower interest rates.

U.S. Government Securities Risk — Although U.S. Government securities are considered to be among the safest investments, they are not guaranteed against price movements due to changing interest rates. Obligations issued by some U.S. Government agencies are backed by the U.S. Treasury, while others are backed solely by the ability of the agency to borrow from the U.S. Treasury or by the agency's own resources.

Investing in the Fund involves risk, and there is no guarantee that the Fund will achieve its investment goal. You could lose money on your investment in the Fund, just as you could with other investments. 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.

Risk Lose Money [Text]

rr_RiskLoseMoney

Investing in the Fund involves risk, and there is no guarantee that the Fund will achieve its investment goal. You could lose money on your investment in the Fund, just as you could with other investments.

Risk Nondiversified Status [Text]

rr_RiskNondiversifiedStatus

The Fund is non-diversified, which means that it may invest in the securities of relatively few issuers. As a result, the Fund may be more susceptible to a single adverse economic or political occurrence affecting one or more of these issuers and may experience increased volatility due to its investments in those securities.

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

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.

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

Performance Information

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The bar chart and the performance table below provide some indication of the risks of investing in the Fund by showing changes in the Fund's performance from year to year for the past ten calendar years and by showing how the Fund's average annual returns for 1, 5 and 10 years, and since the Fund's inception, compare with those of a broad measure of market performance. The performance information shown is based on full calendar years. The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future. For current performance information, please call 1-800-DIAL-SEI.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

The bar chart and the performance table below provide some indication of the risks of investing in the Fund by showing changes in the Fund's performance from year to year for the past ten calendar years and by showing how the Fund's average annual returns for 1, 5 and 10 years, and since the Fund's inception, compare with those of a broad measure of market performance.

Performance Availability Phone [Text]

rr_PerformanceAvailabilityPhone

1-800-DIAL-SEI

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future.

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

Best Quarter: 6.35% (09/30/09)
Worst Quarter: -3.02% (06/30/15)

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Best Quarter:

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Sep. 30, 2009

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

6.35%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Worst Quarter:

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Jun. 30, 2015

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(3.02%)

Performance Table Heading

rr_PerformanceTableHeading

Average Annual Total Returns (for the periods ended December 31, 2017)

Index No Deduction for Fees, Expenses, Taxes [Text]

rr_IndexNoDeductionForFeesExpensesTaxes

(reflects no deduction for fees, expenses or taxes)

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes.

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

Your actual after-tax returns will depend on your tax situation and may differ from those shown. After-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts.

Performance Table Narrative

rr_PerformanceTableNarrativeTextBlock

After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Your actual after-tax returns will depend on your tax situation and may differ from those shown. After-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts.

Class F Prospectus | SIT INTERNATIONAL FIXED INCOME FUND | Bloomberg Barclays Global Aggregate ex-US Index, Hedged Return (reflects no deduction for fees, expenses or taxes)

Risk/Return:

rr_RiskReturnAbstract

Label

rr_AverageAnnualReturnLabel

Bloomberg Barclays Global Aggregate ex-US Index, Hedged Return (reflects no deduction for fees, expenses or taxes)

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

2.48%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

3.70%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

4.23%

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

5.65%

^[1]

Average Annual Returns, Inception Date

rr_AverageAnnualReturnInceptionDate

Sep. 30, 1993

Class F Prospectus | SIT INTERNATIONAL FIXED INCOME FUND | SIT INTERNATIONAL FIXED INCOME FUND - CLASS F, effective 1-31-2017 (formerly Class A)

Risk/Return:

rr_RiskReturnAbstract

Management Fees

rr_ManagementFeesOverAssets

0.30%

Distribution (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

none

Other Expenses

rr_OtherExpensesOverAssets

0.78%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

1.08%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

$ 110

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

343

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

595

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

$ 1,317

Annual Return 2008

rr_AnnualReturn2008

(5.22%)

Annual Return 2009

rr_AnnualReturn2009

11.01%

Annual Return 2010

rr_AnnualReturn2010

5.33%

Annual Return 2011

rr_AnnualReturn2011

3.51%

Annual Return 2012

rr_AnnualReturn2012

6.68%

Annual Return 2013

rr_AnnualReturn2013

(0.11%)

Annual Return 2014

rr_AnnualReturn2014

7.92%

Annual Return 2015

rr_AnnualReturn2015

0.39%

Annual Return 2016

rr_AnnualReturn2016

4.56%

Annual Return 2017

rr_AnnualReturn2017

1.79%

Label

rr_AverageAnnualReturnLabel

Return Before Taxes

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

1.79%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

2.87%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

3.49%

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

4.27%

Average Annual Returns, Inception Date

rr_AverageAnnualReturnInceptionDate

Sep. 01, 1993

Class F Prospectus | SIT INTERNATIONAL FIXED INCOME FUND | SIT INTERNATIONAL FIXED INCOME FUND - CLASS F, effective 1-31-2017 (formerly Class A) | After Taxes on Distributions

Risk/Return:

rr_RiskReturnAbstract

Label

rr_AverageAnnualReturnLabel

Return After Taxes on Distributions

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

1.79%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

1.43%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

1.93%

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

2.71%

Class F Prospectus | SIT INTERNATIONAL FIXED INCOME FUND | SIT INTERNATIONAL FIXED INCOME FUND - CLASS F, effective 1-31-2017 (formerly Class A) | After Taxes on Distributions and Sale of Fund Shares

Risk/Return:

rr_RiskReturnAbstract

Label

rr_AverageAnnualReturnLabel

Return After Taxes on Distributions and Sale of Fund Shares

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

1.02%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

1.53%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

2.03%

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

2.72%

[1] Index returns are shown from September 30, 1993.

XML

Class F Prospectus | SIT EMERGING MARKETS DEBT FUND

SIT EMERGING MARKETS DEBT FUND

Investment Goal

Maximize total return.

Fees and Expenses

The following tables describe the fees and expenses that you may pay if you buy and hold Fund shares.

ANNUAL FUND OPERATING EXPENSES (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses	Class F Prospectus SIT EMERGING MARKETS DEBT FUND SIT EMERGING MARKETS DEBT FUND - CLASS F, effective 1-31-2017 (formerly Class A)
Management Fees	0.85%
Distribution (12b-1) Fees	none
Other Expenses	0.78%
Total Annual Fund Operating Expenses	1.63%

EXAMPLE

This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Fund's operating expenses remain the same.

Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Expense Example	1 Year	3 Years	5 Years	10 Years
Class F Prospectus | SIT EMERGING MARKETS DEBT FUND | SIT EMERGING MARKETS DEBT FUND - CLASS F, effective 1-31-2017 (formerly Class A) | USD ($)	166	514	887	1,933

PORTFOLIO TURNOVER

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 Fund 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.

Principal Investment Strategies

Under normal circumstances, the Emerging Markets Debt Fund will invest at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in fixed income securities of emerging market issuers. The Fund will invest in debt securities of government, government-related and corporate issuers in emerging market countries, as well as entities organized to restructure the outstanding debt of such issuers. The Fund may obtain its exposures by investing directly (e.g., in fixed income securities and other instruments) or indirectly/synthetically (e.g., through the use of derivative instruments, principally futures contracts, forward contracts and swaps and structured securities, such as credit-linked and inflation-linked notes). The Fund may invest in swaps based on a single security or an index of securities, including interest rate swaps, credit default swaps, currency swaps and fully-funded total return swaps. Emerging market countries are those countries that are: (i) characterized as developing or emerging by any of the World Bank, the United Nations, the International Finance Corporation, or the European Bank for Reconstruction and Development; (ii) included in an emerging markets index by a recognized index provider; or (iii) countries with similar developing or emerging characteristics as countries classified as emerging market countries pursuant to sub-paragraph (i) and (ii) above, in each case determined at the time of purchase.

The Fund uses a multi-manager approach, relying upon a number of sub-advisers (each, a Sub-Adviser and collectively, the Sub-Advisers) with differing investment philosophies to manage portions of the Fund's portfolio under the general supervision of SEI Investments Management Corporation (SIMC), the Fund's adviser. The Sub-Advisers will spread the Fund's holdings across a number of countries and industries to limit its exposure to any single emerging market economy and may not invest more than 25% of its assets in any single country. There are no restrictions on the Fund's average portfolio maturity or on the maturity of any specific security. There is no minimum rating standard for the Fund's securities, and the Fund's securities will generally be in the lower or lowest rating categories (including those below the fourth highest rating category by a Nationally Recognized Statistical Rating Organization (NRSRO), commonly referred to as junk bonds).

The Sub-Advisers may seek to enhance the Fund's return by actively managing the Fund's foreign currency exposure. In managing the Fund's currency exposure, the Sub-Advisers buy and sell currencies (i.e., take long or short positions) using derivatives, principally futures, foreign currency forward contracts, options on foreign currencies and currency swaps. The Fund may take long and short positions in foreign currencies in excess of the value of the Fund's assets denominated in a particular currency or when the Fund does not own assets denominated in that currency. The Fund may also engage in currency transactions in an attempt to take advantage of certain inefficiencies in the currency exchange market, to increase its exposure to a foreign currency or to shift exposure to foreign currency fluctuations from one currency to another. In managing the Fund's currency exposure from foreign securities, the Sub-Advisers may buy and sell currencies for hedging or for speculative purposes.

The Fund may also invest in futures contracts, forward contracts and swaps for speculative or hedging purposes. Futures contracts, forward contracts and swaps are used to synthetically obtain exposure to the securities identified above or baskets of such securities and to manage the Fund's interest rate duration and yield curve exposure. These derivatives are also used to mitigate the Fund's overall level of risk and/or the Fund's risk to particular types of securities, currencies or market segments. Interest rate swaps are further used to manage the Fund's yield spread sensitivity. When the Fund seeks to take an active long or short position with respect to the likelihood of an event of default of a security or basket of securities, the Fund may use credit default swaps. The Fund may buy credit default swaps in an attempt to manage credit risk where the Fund has credit exposure to an issuer and the Fund may sell credit default swaps to more efficiently gain credit exposure to such security or basket of securities.

The Fund may purchase shares of exchange-traded funds (ETFs) to gain exposure to a particular portion of the market while awaiting an opportunity to purchase securities or other instruments directly.

Principal Risks

Below Investment Grade Securities (Junk Bonds) Risk — Fixed income securities rated below investment grade (junk bonds) involve greater risks of default or downgrade and are generally more volatile than investment grade securities because the prospect for repayment of principal and interest of many of these securities is speculative. Because these securities typically offer a higher rate of return to compensate investors for these risks, they are sometimes referred to as "high yield bonds," but there is no guarantee that an investment in these securities will result in a high rate of return.

Corporate Fixed Income Securities Risk — Corporate fixed income securities respond to economic developments, especially changes in interest rates, as well as perceptions of the creditworthiness and business prospects of individual issuers.

Credit Risk — The risk that the issuer of a security or the counterparty to a contract will default or otherwise become unable to honor a financial obligation.

Currency Risk — As a result of the Fund's investments in securities or other investments denominated in, and/or receiving revenues in, foreign currencies and the Fund's active management of its currency exposures, the Fund will be subject to currency risk. Currency risk is the risk that foreign currencies will decline in value relative to the U.S. dollar or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency hedged. In either event, the dollar value of an investment in the Fund would be adversely affected. Due to the Fund's active positions in currencies, it will be subject to the risk that currency exchange rates may fluctuate in response to, among other things, changes in interest rates, intervention (or failure to intervene) by U.S. or foreign governments, central banks or supranational entities, or by the imposition of currency controls or other political developments in the United States or abroad.

Derivatives Risk — The Fund's use of futures contracts, forward contracts, options, swaps and credit-linked notes is subject to market risk, leverage risk, correlation risk and liquidity risk. Leverage risk, liquidity risk and market risk are described below. Many over-the-counter (OTC) derivative instruments will not have liquidity beyond the counterparty to the instrument. Correlation risk is the risk that changes in the value of the derivative may not correlate perfectly with the underlying asset, rate or index. The Fund's use of forward contracts, options, credit-linked notes and swap agreements is also subject to credit risk and valuation risk. Valuation risk is the risk that the derivative may be difficult to value and/or valued incorrectly. Credit risk is described above. Each of the above risks could cause the Fund to lose more than the principal amount invested in a derivative instrument. Some derivatives have the potential for unlimited loss, regardless of the size of the Fund's initial investment. The other parties to certain derivative contracts present the same types of credit risk as issuers of fixed income securities. The Fund's use of derivatives may also increase the amount of taxes payable by shareholders. Both U.S. and non-U.S. regulators are in the process of adopting and implementing regulations governing derivatives markets, the ultimate impact of which remains unclear.

Duration Risk — The longer-term securities in which the Fund may invest tend to be more volatile than shorter-term securities. A portfolio with a longer average portfolio duration is more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration.

Exchange-Traded Funds (ETFs) Risk — The risks of owning shares of an ETF generally reflect the risks of owning the underlying securities the ETF is designed to track, although lack of liquidity in an ETF could result in its value being more volatile than the underlying portfolio securities. When the Fund invests in an ETF, in addition to directly bearing the expenses associated with its own operations, it will bear a pro rata portion of the ETF's expenses.

Extension Risk — The risk that rising interest rates may extend the duration of a fixed income security, typically reducing the security's value.

Fixed Income Market Risk — The prices of the Fund's fixed income securities respond to economic developments, particularly interest rate changes, as well as to perceptions about the creditworthiness of individual issuers, including governments and their agencies. Generally, the Fund's fixed income securities will decrease in value if interest rates rise and vice versa. In a low interest rate environment, risks associated with rising rates are heightened. Declines in dealer market-making capacity as a result of structural or regulatory changes could further decrease liquidity and/or increase volatility in the fixed income markets. In the case of foreign securities, price fluctuations will reflect international economic and political events, as well as changes in currency valuations relative to the U.S. dollar. In response to these events, the Fund's value may fluctuate and/or the Fund may experience increased redemptions from shareholders, which may impact the Fund's liquidity or force the Fund to sell securities into a declining or illiquid market.

Foreign Investment/Emerging Markets Risk — The risk that non-U.S. securities may be subject to additional risks due to, among other things, political, social and economic developments abroad, currency movements and different legal, regulatory and tax environments. These additional risks may be heightened with respect to emerging market countries because political turmoil and rapid changes in economic conditions are more likely to occur in these countries.

Foreign Sovereign Debt Securities Risk — The risks that (i) the governmental entity that controls the repayment of sovereign debt may not be willing or able to repay the principal and/or interest when it becomes due because of factors such as debt service burden, political constraints, cash flow problems and other national economic factors; (ii) governments may default on their debt securities, which may require holders of such securities to participate in debt rescheduling or additional lending to defaulting governments; and (iii) there is no bankruptcy proceeding by which defaulted sovereign debt may be collected in whole or in part.

Interest Rate Risk — The risk that a rise in interest rates will cause a fall in the value of fixed income securities in which the Fund invests. A low interest rate environment may present greater interest rate risk, because there may be a greater likelihood of rates increasing and rates may increase more rapidly.

Investment Style Risk — The risk that emerging market debt securities may underperform other segments of the fixed income markets or the fixed income markets as a whole.

Leverage Risk — The Fund's use of derivatives may result in the Fund's total investment exposure substantially exceeding the value of its portfolio securities and the Fund's investment returns depending substantially on the performance of securities that the Fund may not directly own. The use of leverage can amplify the effects of market volatility on the Fund's share price and may also cause the Fund to liquidate portfolio positions when it would not be advantageous to do so in order to satisfy its obligations. The Fund's use of leverage may result in a heightened risk of investment loss.

Liquidity Risk — The risk that certain securities may be difficult or impossible to sell at the time and the price that the Fund would like. The Fund may have to lower the price of the security, sell other securities instead or forego an investment opportunity, any of which could have a negative effect on Fund management or performance.

Market Risk — The risk that the market value of a security may move up and down, sometimes rapidly and unpredictably. Market risk may affect a single issuer, an industry, a sector or the equity or bond market as a whole.

Non-Diversified Risk — The Fund is non-diversified, which means that it may invest in the securities of relatively few issuers. As a result, the Fund may be more susceptible to a single adverse economic or political occurrence affecting one or more of these issuers and may experience increased volatility due to its investments in those securities.

Prepayment Risk — The risk that in a declining interest rate environment, fixed income securities with stated interest rates may have the principal paid earlier than expected, requiring the Fund to invest the proceeds at generally lower interest rates.

Investing in the Fund involves risk, and there is no guarantee that the Fund will achieve its investment goal. You could lose money on your investment in the Fund, just as you could with other investments. 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.

Performance Information

The bar chart and the performance table below provide some indication of the risks of investing in the Fund by showing changes in the Fund's performance from year to year for the past ten calendar years and by showing how the Fund's average annual returns for 1, 5 and 10 years, and since the Fund's inception, compare with those of a broad measure of market performance. The performance information shown is based on full calendar years. The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future. For current performance information, please call 1-800-DIAL-SEI.

Best Quarter: 15.11% (06/30/09)
Worst Quarter: -13.19% (12/31/08)

Average Annual Total Returns (for the periods ended December 31, 2017)

This table compares the Fund's average annual total returns to those of a broad-based index and the Fund's 50/50 Blended Benchmark, which consists of the J.P. Morgan Emerging Markets Bond Index (EMBI) Global Diversified Index (50%) and the J.P. Morgan Government Bond Index-Emerging Markets (GBI-EM) Global Diversified Index (50%). The Fund's Blended Benchmark is designed to provide a useful comparison to the Fund's overall performance and more accurately reflect the Fund's investment strategy than the broad-based index.

After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Your actual after-tax returns will depend on your tax situation and may differ from those shown. After-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts.

Average Annual Returns - Class F Prospectus - SIT EMERGING MARKETS DEBT FUND	Label	Average Annual Returns, 1 Year	Average Annual Returns, 5 Years	Average Annual Returns, 10 Years	Average Annual Returns, Since Inception		Average Annual Returns, Inception Date
SIT EMERGING MARKETS DEBT FUND - CLASS F, effective 1-31-2017 (formerly Class A)	Return Before Taxes	14.25%	0.29%	4.90%	8.18%		Jun. 26, 1997
After Taxes on Distributions | SIT EMERGING MARKETS DEBT FUND - CLASS F, effective 1-31-2017 (formerly Class A)	Return After Taxes on Distributions	12.36%	(0.80%)	3.07%	5.40%
After Taxes on Distributions and Sale of Fund Shares | SIT EMERGING MARKETS DEBT FUND - CLASS F, effective 1-31-2017 (formerly Class A)	Return After Taxes on Distributions and Sale of Fund Shares	8.05%	(0.28%)	3.11%	5.37%
J.P. Morgan EMBI Global Diversified Index Return (reflects no deduction for fees, expenses or taxes)	J.P. Morgan EMBI Global Diversified Index Return (reflects no deduction for fees, expenses or taxes)	10.26%	4.58%	7.29%	8.71%	[1]	Jun. 30, 1997
The Fund's Blended Benchmark Return (reflects no deduction for fees, expenses or taxes)	The Fund's Blended Benchmark Return (reflects no deduction for fees, expenses or taxes)	12.74%	1.53%	5.49%		[1],[2]	Jun. 30, 1997

[1] Index returns are shown from June 30, 1997.

[2] The Blended Benchmark Return for the "Since Inception" period is not provided because returns for the J.P. Morgan GBI-EM Global Diversified Index Return are not available prior to 2003.

XML

Label

Element

Value

Class F Prospectus | SIT EMERGING MARKETS DEBT FUND

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

SIT EMERGING MARKETS DEBT FUND

Objective [Heading]

rr_ObjectiveHeading

Investment Goal

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

Maximize total return.

Expense [Heading]

rr_ExpenseHeading

Fees and Expenses

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

The following tables describe the fees and expenses that you may pay if you buy and hold Fund shares.

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

ANNUAL FUND OPERATING EXPENSES (expenses that you pay each year as a percentage of the value of your investment)

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

PORTFOLIO TURNOVER

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 Fund 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 [Heading]

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EXAMPLE

Expense Example Narrative [Text Block]

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This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Fund's operating expenses remain the same.

Expense Example by, Year, Caption [Text]

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Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Strategy [Heading]

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Principal Investment Strategies

Strategy Narrative [Text Block]

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Under normal circumstances, the Emerging Markets Debt Fund will invest at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in fixed income securities of emerging market issuers. The Fund will invest in debt securities of government, government-related and corporate issuers in emerging market countries, as well as entities organized to restructure the outstanding debt of such issuers. The Fund may obtain its exposures by investing directly (e.g., in fixed income securities and other instruments) or indirectly/synthetically (e.g., through the use of derivative instruments, principally futures contracts, forward contracts and swaps and structured securities, such as credit-linked and inflation-linked notes). The Fund may invest in swaps based on a single security or an index of securities, including interest rate swaps, credit default swaps, currency swaps and fully-funded total return swaps. Emerging market countries are those countries that are: (i) characterized as developing or emerging by any of the World Bank, the United Nations, the International Finance Corporation, or the European Bank for Reconstruction and Development; (ii) included in an emerging markets index by a recognized index provider; or (iii) countries with similar developing or emerging characteristics as countries classified as emerging market countries pursuant to sub-paragraph (i) and (ii) above, in each case determined at the time of purchase.

The Fund uses a multi-manager approach, relying upon a number of sub-advisers (each, a Sub-Adviser and collectively, the Sub-Advisers) with differing investment philosophies to manage portions of the Fund's portfolio under the general supervision of SEI Investments Management Corporation (SIMC), the Fund's adviser. The Sub-Advisers will spread the Fund's holdings across a number of countries and industries to limit its exposure to any single emerging market economy and may not invest more than 25% of its assets in any single country. There are no restrictions on the Fund's average portfolio maturity or on the maturity of any specific security. There is no minimum rating standard for the Fund's securities, and the Fund's securities will generally be in the lower or lowest rating categories (including those below the fourth highest rating category by a Nationally Recognized Statistical Rating Organization (NRSRO), commonly referred to as junk bonds).

The Sub-Advisers may seek to enhance the Fund's return by actively managing the Fund's foreign currency exposure. In managing the Fund's currency exposure, the Sub-Advisers buy and sell currencies (i.e., take long or short positions) using derivatives, principally futures, foreign currency forward contracts, options on foreign currencies and currency swaps. The Fund may take long and short positions in foreign currencies in excess of the value of the Fund's assets denominated in a particular currency or when the Fund does not own assets denominated in that currency. The Fund may also engage in currency transactions in an attempt to take advantage of certain inefficiencies in the currency exchange market, to increase its exposure to a foreign currency or to shift exposure to foreign currency fluctuations from one currency to another. In managing the Fund's currency exposure from foreign securities, the Sub-Advisers may buy and sell currencies for hedging or for speculative purposes.

The Fund may also invest in futures contracts, forward contracts and swaps for speculative or hedging purposes. Futures contracts, forward contracts and swaps are used to synthetically obtain exposure to the securities identified above or baskets of such securities and to manage the Fund's interest rate duration and yield curve exposure. These derivatives are also used to mitigate the Fund's overall level of risk and/or the Fund's risk to particular types of securities, currencies or market segments. Interest rate swaps are further used to manage the Fund's yield spread sensitivity. When the Fund seeks to take an active long or short position with respect to the likelihood of an event of default of a security or basket of securities, the Fund may use credit default swaps. The Fund may buy credit default swaps in an attempt to manage credit risk where the Fund has credit exposure to an issuer and the Fund may sell credit default swaps to more efficiently gain credit exposure to such security or basket of securities.

The Fund may purchase shares of exchange-traded funds (ETFs) to gain exposure to a particular portion of the market while awaiting an opportunity to purchase securities or other instruments directly.

Risk [Heading]

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Principal Risks

Risk Narrative [Text Block]

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Below Investment Grade Securities (Junk Bonds) Risk — Fixed income securities rated below investment grade (junk bonds) involve greater risks of default or downgrade and are generally more volatile than investment grade securities because the prospect for repayment of principal and interest of many of these securities is speculative. Because these securities typically offer a higher rate of return to compensate investors for these risks, they are sometimes referred to as "high yield bonds," but there is no guarantee that an investment in these securities will result in a high rate of return.

Corporate Fixed Income Securities Risk — Corporate fixed income securities respond to economic developments, especially changes in interest rates, as well as perceptions of the creditworthiness and business prospects of individual issuers.

Credit Risk — The risk that the issuer of a security or the counterparty to a contract will default or otherwise become unable to honor a financial obligation.

Currency Risk — As a result of the Fund's investments in securities or other investments denominated in, and/or receiving revenues in, foreign currencies and the Fund's active management of its currency exposures, the Fund will be subject to currency risk. Currency risk is the risk that foreign currencies will decline in value relative to the U.S. dollar or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency hedged. In either event, the dollar value of an investment in the Fund would be adversely affected. Due to the Fund's active positions in currencies, it will be subject to the risk that currency exchange rates may fluctuate in response to, among other things, changes in interest rates, intervention (or failure to intervene) by U.S. or foreign governments, central banks or supranational entities, or by the imposition of currency controls or other political developments in the United States or abroad.

Derivatives Risk — The Fund's use of futures contracts, forward contracts, options, swaps and credit-linked notes is subject to market risk, leverage risk, correlation risk and liquidity risk. Leverage risk, liquidity risk and market risk are described below. Many over-the-counter (OTC) derivative instruments will not have liquidity beyond the counterparty to the instrument. Correlation risk is the risk that changes in the value of the derivative may not correlate perfectly with the underlying asset, rate or index. The Fund's use of forward contracts, options, credit-linked notes and swap agreements is also subject to credit risk and valuation risk. Valuation risk is the risk that the derivative may be difficult to value and/or valued incorrectly. Credit risk is described above. Each of the above risks could cause the Fund to lose more than the principal amount invested in a derivative instrument. Some derivatives have the potential for unlimited loss, regardless of the size of the Fund's initial investment. The other parties to certain derivative contracts present the same types of credit risk as issuers of fixed income securities. The Fund's use of derivatives may also increase the amount of taxes payable by shareholders. Both U.S. and non-U.S. regulators are in the process of adopting and implementing regulations governing derivatives markets, the ultimate impact of which remains unclear.

Duration Risk — The longer-term securities in which the Fund may invest tend to be more volatile than shorter-term securities. A portfolio with a longer average portfolio duration is more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration.

Exchange-Traded Funds (ETFs) Risk — The risks of owning shares of an ETF generally reflect the risks of owning the underlying securities the ETF is designed to track, although lack of liquidity in an ETF could result in its value being more volatile than the underlying portfolio securities. When the Fund invests in an ETF, in addition to directly bearing the expenses associated with its own operations, it will bear a pro rata portion of the ETF's expenses.

Extension Risk — The risk that rising interest rates may extend the duration of a fixed income security, typically reducing the security's value.

Fixed Income Market Risk — The prices of the Fund's fixed income securities respond to economic developments, particularly interest rate changes, as well as to perceptions about the creditworthiness of individual issuers, including governments and their agencies. Generally, the Fund's fixed income securities will decrease in value if interest rates rise and vice versa. In a low interest rate environment, risks associated with rising rates are heightened. Declines in dealer market-making capacity as a result of structural or regulatory changes could further decrease liquidity and/or increase volatility in the fixed income markets. In the case of foreign securities, price fluctuations will reflect international economic and political events, as well as changes in currency valuations relative to the U.S. dollar. In response to these events, the Fund's value may fluctuate and/or the Fund may experience increased redemptions from shareholders, which may impact the Fund's liquidity or force the Fund to sell securities into a declining or illiquid market.

Foreign Investment/Emerging Markets Risk — The risk that non-U.S. securities may be subject to additional risks due to, among other things, political, social and economic developments abroad, currency movements and different legal, regulatory and tax environments. These additional risks may be heightened with respect to emerging market countries because political turmoil and rapid changes in economic conditions are more likely to occur in these countries.

Foreign Sovereign Debt Securities Risk — The risks that (i) the governmental entity that controls the repayment of sovereign debt may not be willing or able to repay the principal and/or interest when it becomes due because of factors such as debt service burden, political constraints, cash flow problems and other national economic factors; (ii) governments may default on their debt securities, which may require holders of such securities to participate in debt rescheduling or additional lending to defaulting governments; and (iii) there is no bankruptcy proceeding by which defaulted sovereign debt may be collected in whole or in part.

Interest Rate Risk — The risk that a rise in interest rates will cause a fall in the value of fixed income securities in which the Fund invests. A low interest rate environment may present greater interest rate risk, because there may be a greater likelihood of rates increasing and rates may increase more rapidly.

Investment Style Risk — The risk that emerging market debt securities may underperform other segments of the fixed income markets or the fixed income markets as a whole.

Leverage Risk — The Fund's use of derivatives may result in the Fund's total investment exposure substantially exceeding the value of its portfolio securities and the Fund's investment returns depending substantially on the performance of securities that the Fund may not directly own. The use of leverage can amplify the effects of market volatility on the Fund's share price and may also cause the Fund to liquidate portfolio positions when it would not be advantageous to do so in order to satisfy its obligations. The Fund's use of leverage may result in a heightened risk of investment loss.

Liquidity Risk — The risk that certain securities may be difficult or impossible to sell at the time and the price that the Fund would like. The Fund may have to lower the price of the security, sell other securities instead or forego an investment opportunity, any of which could have a negative effect on Fund management or performance.

Market Risk — The risk that the market value of a security may move up and down, sometimes rapidly and unpredictably. Market risk may affect a single issuer, an industry, a sector or the equity or bond market as a whole.

Non-Diversified Risk — The Fund is non-diversified, which means that it may invest in the securities of relatively few issuers. As a result, the Fund may be more susceptible to a single adverse economic or political occurrence affecting one or more of these issuers and may experience increased volatility due to its investments in those securities.

Prepayment Risk — The risk that in a declining interest rate environment, fixed income securities with stated interest rates may have the principal paid earlier than expected, requiring the Fund to invest the proceeds at generally lower interest rates.

Investing in the Fund involves risk, and there is no guarantee that the Fund will achieve its investment goal. You could lose money on your investment in the Fund, just as you could with other investments. 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.

Risk Lose Money [Text]

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Investing in the Fund involves risk, and there is no guarantee that the Fund will achieve its investment goal. You could lose money on your investment in the Fund, just as you could with other investments.

Risk Nondiversified Status [Text]

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The Fund is non-diversified, which means that it may invest in the securities of relatively few issuers. As a result, the Fund may be more susceptible to a single adverse economic or political occurrence affecting one or more of these issuers and may experience increased volatility due to its investments in those securities.

Risk Not Insured Depository Institution [Text]

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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.

Bar Chart and Performance Table [Heading]

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Performance Information

Performance Narrative [Text Block]

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The bar chart and the performance table below provide some indication of the risks of investing in the Fund by showing changes in the Fund's performance from year to year for the past ten calendar years and by showing how the Fund's average annual returns for 1, 5 and 10 years, and since the Fund's inception, compare with those of a broad measure of market performance. The performance information shown is based on full calendar years. The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future. For current performance information, please call 1-800-DIAL-SEI.

Performance Information Illustrates Variability of Returns [Text]

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The bar chart and the performance table below provide some indication of the risks of investing in the Fund by showing changes in the Fund's performance from year to year for the past ten calendar years and by showing how the Fund's average annual returns for 1, 5 and 10 years, and since the Fund's inception, compare with those of a broad measure of market performance.

Performance Additional Market Index [Text]

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This table compares the Fund's average annual total returns to those of a broad-based index and the Fund's 50/50 Blended Benchmark, which consists of the J.P. Morgan Emerging Markets Bond Index (EMBI) Global Diversified Index (50%) and the J.P. Morgan Government Bond Index-Emerging Markets (GBI-EM) Global Diversified Index (50%). The Fund's Blended Benchmark is designed to provide a useful comparison to the Fund's overall performance and more accurately reflect the Fund's investment strategy than the broad-based index.

Performance Availability Phone [Text]

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1-800-DIAL-SEI

Performance Past Does Not Indicate Future [Text]

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The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future.

Bar Chart Closing [Text Block]

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Best Quarter: 15.11% (06/30/09)
Worst Quarter: -13.19% (12/31/08)

Highest Quarterly Return, Label

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Best Quarter:

Highest Quarterly Return, Date

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Jun. 30, 2009

Highest Quarterly Return

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15.11%

Lowest Quarterly Return, Label

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Worst Quarter:

Lowest Quarterly Return, Date

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Dec. 31, 2008

Lowest Quarterly Return

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(13.19%)

Performance Table Heading

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Average Annual Total Returns (for the periods ended December 31, 2017)

Index No Deduction for Fees, Expenses, Taxes [Text]

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(reflects no deduction for fees, expenses or taxes)

Performance Table Uses Highest Federal Rate

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After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes.

Performance Table Not Relevant to Tax Deferred

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Your actual after-tax returns will depend on your tax situation and may differ from those shown. After-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts.

Performance Table Narrative

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This table compares the Fund's average annual total returns to those of a broad-based index and the Fund's 50/50 Blended Benchmark, which consists of the J.P. Morgan Emerging Markets Bond Index (EMBI) Global Diversified Index (50%) and the J.P. Morgan Government Bond Index-Emerging Markets (GBI-EM) Global Diversified Index (50%). The Fund's Blended Benchmark is designed to provide a useful comparison to the Fund's overall performance and more accurately reflect the Fund's investment strategy than the broad-based index.

After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Your actual after-tax returns will depend on your tax situation and may differ from those shown. After-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts.

Class F Prospectus | SIT EMERGING MARKETS DEBT FUND | J.P. Morgan EMBI Global Diversified Index Return (reflects no deduction for fees, expenses or taxes)

Risk/Return:

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Label

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J.P. Morgan EMBI Global Diversified Index Return (reflects no deduction for fees, expenses or taxes)

Average Annual Returns, 1 Year

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10.26%

Average Annual Returns, 5 Years

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4.58%

Average Annual Returns, 10 Years

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7.29%

Average Annual Returns, Since Inception

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8.71%

^[1]

Average Annual Returns, Inception Date

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Jun. 30, 1997

Class F Prospectus | SIT EMERGING MARKETS DEBT FUND | The Fund's Blended Benchmark Return (reflects no deduction for fees, expenses or taxes)

Risk/Return:

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Label

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The Fund's Blended Benchmark Return (reflects no deduction for fees, expenses or taxes)

Average Annual Returns, 1 Year

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12.74%

Average Annual Returns, 5 Years

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1.53%

Average Annual Returns, 10 Years

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5.49%

Average Annual Returns, Since Inception

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^[1],[2]

Average Annual Returns, Inception Date

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Jun. 30, 1997

Class F Prospectus | SIT EMERGING MARKETS DEBT FUND | SIT EMERGING MARKETS DEBT FUND - CLASS F, effective 1-31-2017 (formerly Class A)

Risk/Return:

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Management Fees

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0.85%

Distribution (12b-1) Fees

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none

Other Expenses

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0.78%

Total Annual Fund Operating Expenses

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1.63%

Expense Example, with Redemption, 1 Year

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$ 166

Expense Example, with Redemption, 3 Years

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514

Expense Example, with Redemption, 5 Years

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887

Expense Example, with Redemption, 10 Years

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$ 1,933

Annual Return 2008

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(19.72%)

Annual Return 2009

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40.53%

Annual Return 2010

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14.47%

Annual Return 2011

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4.74%

Annual Return 2012

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17.54%

Annual Return 2013

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(9.59%)

Annual Return 2014

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(1.20%)

Annual Return 2015

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(9.12%)

Annual Return 2016

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9.40%

Annual Return 2017

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14.25%

Label

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Return Before Taxes

Average Annual Returns, 1 Year

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14.25%

Average Annual Returns, 5 Years

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0.29%

Average Annual Returns, 10 Years

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4.90%

Average Annual Returns, Since Inception

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8.18%

Average Annual Returns, Inception Date

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Jun. 26, 1997

Class F Prospectus | SIT EMERGING MARKETS DEBT FUND | SIT EMERGING MARKETS DEBT FUND - CLASS F, effective 1-31-2017 (formerly Class A) | After Taxes on Distributions

Risk/Return:

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Label

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Return After Taxes on Distributions

Average Annual Returns, 1 Year

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12.36%

Average Annual Returns, 5 Years

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(0.80%)

Average Annual Returns, 10 Years

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3.07%

Average Annual Returns, Since Inception

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5.40%

Class F Prospectus | SIT EMERGING MARKETS DEBT FUND | SIT EMERGING MARKETS DEBT FUND - CLASS F, effective 1-31-2017 (formerly Class A) | After Taxes on Distributions and Sale of Fund Shares

Risk/Return:

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Label

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Return After Taxes on Distributions and Sale of Fund Shares

Average Annual Returns, 1 Year

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8.05%

Average Annual Returns, 5 Years

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(0.28%)

Average Annual Returns, 10 Years

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3.11%

Average Annual Returns, Since Inception

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5.37%

[1] Index returns are shown from June 30, 1997.

[2] The Blended Benchmark Return for the "Since Inception" period is not provided because returns for the J.P. Morgan GBI-EM Global Diversified Index Return are not available prior to 2003.

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Class I Prospectus | SIT INTERNATIONAL EQUITY FUND

SIT INTERNATIONAL EQUITY FUND

Investment Goal

Long-term capital appreciation.

Fees and Expenses

The following tables describe the fees and expenses that you may pay if you buy and hold Fund shares.

ANNUAL FUND OPERATING EXPENSES (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses	Class I Prospectus SIT INTERNATIONAL EQUITY FUND SIT INTERNATIONAL EQUITY FUND - CLASS I
Management Fees	0.51%
Distribution (12b-1) Fees	none
Other Expenses	0.89%
Total Annual Fund Operating Expenses	1.40%

EXAMPLE

This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Fund's operating expenses remain the same.

Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Expense Example	1 Year	3 Years	5 Years	10 Years
Class I Prospectus | SIT INTERNATIONAL EQUITY FUND | SIT INTERNATIONAL EQUITY FUND - CLASS I | USD ($)	143	443	766	1,680

PORTFOLIO TURNOVER

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 Fund operating expenses or in the Example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 57% of the average value of its portfolio.

Principal Investment Strategies

Under normal circumstances, the International Equity Fund will invest at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in equity securities. Equity securities may include common stocks, preferred stock, warrants, participation notes and depositary receipts. The Fund will invest primarily in equity securities of issuers of all capitalization ranges that are located in at least three countries other than the U.S. It is expected that at least 40% of the Fund's assets will be invested outside the U.S. The Fund will invest primarily in companies located in developed countries, but may also invest in companies located in emerging markets. Generally, the Fund will invest less than 20% of its assets in emerging markets. Emerging market countries are those countries that are: (i) characterized as developing or emerging by any of the World Bank, the United Nations, the International Finance Corporation, or the European Bank for Reconstruction and Development; (ii) included in an emerging markets index by a recognized index provider; or (iii) countries with similar developing or emerging characteristics as countries classified as emerging market countries pursuant to sub-paragraph (i) and (ii) above, in each case determined at the time of purchase.

The Fund uses a multi-manager approach, relying upon a number of sub-advisers (each, a Sub-Adviser and collectively, the Sub-Advisers) with differing investment philosophies to manage portions of the Fund's portfolio under the general supervision of SEI Investments Management Corporation (SIMC), the Fund's adviser.

The Fund may invest in futures contracts, forward contracts and options for hedging purposes, including seeking to manage the Fund's currency exposure to foreign securities and mitigate the Fund's overall risk.

The Fund may purchase futures contracts or shares of exchange-traded funds (ETFs) to gain exposure to a particular portion of the market while awaiting an opportunity to purchase securities or other instruments directly.

Principal Risks

Credit Risk — The risk that the issuer of a security or the counterparty to a contract will default or otherwise become unable to honor a financial obligation.

Currency Risk — As a result of the Fund's investments in securities denominated in, and/or receiving revenues in, foreign currencies, the Fund will be subject to currency risk. Currency risk is the risk that foreign currencies will decline in value relative to the U.S. dollar or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency hedged. In either event, the dollar value of an investment in the Fund would be adversely affected. Currency exchange rates may fluctuate in response to, among other things, changes in interest rates, intervention (or failure to intervene) by U.S. or foreign governments, central banks or supranational entities, or by the imposition of currency controls or other political developments in the United States or abroad.

Depositary Receipts Risk — Depositary receipts, such as American Depositary Receipts (ADRs), are certificates evidencing ownership of shares of a foreign issuer that are issued by depositary banks and generally trade on an established market. Depositary receipts are subject to many of the risks associated with investing directly in foreign securities, including, among other things, political, social and economic developments abroad, currency movements and different legal, regulatory and tax environments.

Derivatives Risk — The Fund's use of futures contracts, forward contracts and options is subject to market risk, leverage risk, correlation risk and liquidity risk. Leverage risk, liquidity risk and market risk are described below. Many over-the-counter (OTC) derivative instruments will not have liquidity beyond the counterparty to the instrument. Correlation risk is the risk that changes in the value of the derivative may not correlate perfectly with the underlying asset, rate or index. The Fund's use of forward contracts is also subject to credit risk and valuation risk. Valuation risk is the risk that the derivative may be difficult to value and/or valued incorrectly. Credit risk is described above. Each of the above risks could cause the Fund to lose more than the principal amount invested in a derivative instrument. Some derivatives have the potential for unlimited loss, regardless of the size of the Fund's initial investment. The other parties to certain derivative contracts present the same types of credit risk as issuers of fixed income securities. The Fund's use of derivatives may also increase the amount of taxes payable by shareholders. Both U.S. and non-U.S. regulators are in the process of adopting and implementing regulations governing derivatives markets, the ultimate impact of which remains unclear.

Equity Market Risk — The risk that stock prices will fall over short or extended periods of time.

Exchange-Traded Funds (ETFs) Risk — The risks of owning shares of an ETF generally reflect the risks of owning the underlying securities the ETF is designed to track, although lack of liquidity in an ETF could result in its value being more volatile than the underlying portfolio securities. When the Fund invests in an ETF, in addition to directly bearing the expenses associated with its own operations, it will bear a pro rata portion of the ETF's expenses.

Foreign Investment/Emerging Markets Risk — The risk that non-U.S. securities may be subject to additional risks due to, among other things, political, social and economic developments abroad, currency movements and different legal, regulatory and tax environments. These additional risks may be heightened with respect to emerging market countries because political turmoil and rapid changes in economic conditions are more likely to occur in these countries.

Investment Style Risk — The risk that developed international equity securities may underperform other segments of the equity markets or the equity markets as a whole.

Leverage Risk — The Fund's use of derivatives may result in the Fund's total investment exposure substantially exceeding the value of its portfolio securities and the Fund's investment returns depending substantially on the performance of securities that the Fund may not directly own. The use of leverage can amplify the effects of market volatility on the Fund's share price and may also cause the Fund to liquidate portfolio positions when it would not be advantageous to do so in order to satisfy its obligations. The Fund's use of leverage may result in a heightened risk of investment loss.

Liquidity Risk — The risk that certain securities may be difficult or impossible to sell at the time and the price that the Fund would like. The Fund may have to lower the price of the security, sell other securities instead or forego an investment opportunity, any of which could have a negative effect on Fund management or performance.

Market Risk — The risk that the market value of a security may move up and down, sometimes rapidly and unpredictably. Market risk may affect a single issuer, an industry, a sector or the equity or bond market as a whole.

Participation Notes (P-Notes) Risk — P-Notes are participation interest notes that are issued by banks or broker-dealers and are designed to offer a return linked to a particular underlying equity, debt, currency or market. Investments in P-Notes involve the same risks associated with a direct investment in the underlying foreign companies or foreign securities markets that they seek to replicate. However, there can be no assurance that the trading price of P-Notes will equal the underlying value of the foreign companies or foreign securities markets that they seek to replicate.

Small and Medium Capitalization Risk — The risk that small and medium capitalization companies in which the Fund may invest may be more vulnerable to adverse business or economic events than larger, more established companies. In particular, small and medium capitalization companies may have limited product lines, markets and financial resources and may depend upon a relatively small management group. Therefore, small capitalization and medium capitalization stocks may be more volatile than those of larger companies. Small capitalization and medium capitalization stocks may be traded OTC or listed on an exchange.

Warrants Risk — Warrants are instruments that entitle the holder to buy an equity security at a specific price for a specific period of time. Warrants may be more speculative than other types of investments. The price of a warrant may be more volatile than the price of its underlying security, and a warrant may offer greater potential for capital appreciation as well as capital loss. A warrant ceases to have value if it is not exercised prior to its expiration date.

Investing in the Fund involves risk, and there is no guarantee that the Fund will achieve its investment goal. You could lose money on your investment in the Fund, just as you could with other investments. 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.

Performance Information

The bar chart and the performance table below provide some indication of the risks of investing in the Fund by showing changes in the Fund's performance from year to year for the past ten calendar years and by showing how the Fund's average annual returns for 1, 5 and 10 years, and since the Fund's inception, compare with those of a broad measure of market performance. The performance information shown is based on full calendar years. The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future. For current performance information, please call 1-800-DIAL-SEI.

Best Quarter: 22.94% (06/30/09)
Worst Quarter: -26.25% (09/30/08)

Average Annual Total Returns (for the periods ended December 31, 2017)

After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Your actual after-tax returns will depend on your tax situation and may differ from those shown. After-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts. In the event of negative performance, the Fund's returns after taxes on distributions and sale of Fund shares are calculated assuming that an investor has sufficient capital gains of the same character from other investments to offset any capital losses from the sale of Fund shares. As a result, the Fund's returns after taxes on distributions and sale of Fund shares may exceed the Fund's returns before taxes and/or returns after taxes on distributions.

Average Annual Returns - Class I Prospectus - SIT INTERNATIONAL EQUITY FUND	Label	Average Annual Returns, 1 Year		Average Annual Returns, 5 Years		Average Annual Returns, 10 Years		Average Annual Returns, Since Inception		Average Annual Returns, Inception Date
SIT INTERNATIONAL EQUITY FUND - CLASS I	Return Before Taxes	26.31%	[1]	7.63%	[1]	(0.24%)	[1]	3.65%	[1]	Dec. 20, 1989
After Taxes on Distributions | SIT INTERNATIONAL EQUITY FUND - CLASS I	Return After Taxes on Distributions	25.79%	[1]	7.36%	[1]	(0.40%)	[1]	2.83%	[1]
After Taxes on Distributions and Sale of Fund Shares | SIT INTERNATIONAL EQUITY FUND - CLASS I	Return After Taxes on Distributions and Sale of Fund Shares	14.89%	[1]	5.97%	[1]	(0.14%)	[1]	2.76%	[1]
MSCI EAFE Index Return (reflects no deduction for fees, expenses or taxes)	MSCI EAFE Index Return (reflects no deduction for fees, expenses or taxes)	25.03%		7.90%		1.94%		4.68%	[2]	Dec. 31, 1989

[1] The Fund's Class I Shares commenced operations on January 4, 2002. Therefore, the Fund's average annual total returns for the periods prior to that time are based on the average annual total returns of the Class F Shares, adjusted for the higher expenses of the Class I Shares.

[2] Index returns are shown from December 31, 1989.

XML

Label

Element

Value

Class I Prospectus | SIT INTERNATIONAL EQUITY FUND

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

SIT INTERNATIONAL EQUITY FUND

Objective [Heading]

rr_ObjectiveHeading

Investment Goal

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

Long-term capital appreciation.

Expense [Heading]

rr_ExpenseHeading

Fees and Expenses

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

The following tables describe the fees and expenses that you may pay if you buy and hold Fund shares.

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

ANNUAL FUND OPERATING EXPENSES (expenses that you pay each year as a percentage of the value of your investment)

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

PORTFOLIO TURNOVER

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 Fund operating expenses or in the Example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 57% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

57.00%

Expense Example [Heading]

rr_ExpenseExampleHeading

EXAMPLE

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Fund's operating expenses remain the same.

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Strategy [Heading]

rr_StrategyHeading

Principal Investment Strategies

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

Under normal circumstances, the International Equity Fund will invest at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in equity securities. Equity securities may include common stocks, preferred stock, warrants, participation notes and depositary receipts. The Fund will invest primarily in equity securities of issuers of all capitalization ranges that are located in at least three countries other than the U.S. It is expected that at least 40% of the Fund's assets will be invested outside the U.S. The Fund will invest primarily in companies located in developed countries, but may also invest in companies located in emerging markets. Generally, the Fund will invest less than 20% of its assets in emerging markets. Emerging market countries are those countries that are: (i) characterized as developing or emerging by any of the World Bank, the United Nations, the International Finance Corporation, or the European Bank for Reconstruction and Development; (ii) included in an emerging markets index by a recognized index provider; or (iii) countries with similar developing or emerging characteristics as countries classified as emerging market countries pursuant to sub-paragraph (i) and (ii) above, in each case determined at the time of purchase.

The Fund uses a multi-manager approach, relying upon a number of sub-advisers (each, a Sub-Adviser and collectively, the Sub-Advisers) with differing investment philosophies to manage portions of the Fund's portfolio under the general supervision of SEI Investments Management Corporation (SIMC), the Fund's adviser.

The Fund may invest in futures contracts, forward contracts and options for hedging purposes, including seeking to manage the Fund's currency exposure to foreign securities and mitigate the Fund's overall risk.

The Fund may purchase futures contracts or shares of exchange-traded funds (ETFs) to gain exposure to a particular portion of the market while awaiting an opportunity to purchase securities or other instruments directly.

Risk [Heading]

rr_RiskHeading

Principal Risks

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

Credit Risk — The risk that the issuer of a security or the counterparty to a contract will default or otherwise become unable to honor a financial obligation.

Currency Risk — As a result of the Fund's investments in securities denominated in, and/or receiving revenues in, foreign currencies, the Fund will be subject to currency risk. Currency risk is the risk that foreign currencies will decline in value relative to the U.S. dollar or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency hedged. In either event, the dollar value of an investment in the Fund would be adversely affected. Currency exchange rates may fluctuate in response to, among other things, changes in interest rates, intervention (or failure to intervene) by U.S. or foreign governments, central banks or supranational entities, or by the imposition of currency controls or other political developments in the United States or abroad.

Depositary Receipts Risk — Depositary receipts, such as American Depositary Receipts (ADRs), are certificates evidencing ownership of shares of a foreign issuer that are issued by depositary banks and generally trade on an established market. Depositary receipts are subject to many of the risks associated with investing directly in foreign securities, including, among other things, political, social and economic developments abroad, currency movements and different legal, regulatory and tax environments.

Derivatives Risk — The Fund's use of futures contracts, forward contracts and options is subject to market risk, leverage risk, correlation risk and liquidity risk. Leverage risk, liquidity risk and market risk are described below. Many over-the-counter (OTC) derivative instruments will not have liquidity beyond the counterparty to the instrument. Correlation risk is the risk that changes in the value of the derivative may not correlate perfectly with the underlying asset, rate or index. The Fund's use of forward contracts is also subject to credit risk and valuation risk. Valuation risk is the risk that the derivative may be difficult to value and/or valued incorrectly. Credit risk is described above. Each of the above risks could cause the Fund to lose more than the principal amount invested in a derivative instrument. Some derivatives have the potential for unlimited loss, regardless of the size of the Fund's initial investment. The other parties to certain derivative contracts present the same types of credit risk as issuers of fixed income securities. The Fund's use of derivatives may also increase the amount of taxes payable by shareholders. Both U.S. and non-U.S. regulators are in the process of adopting and implementing regulations governing derivatives markets, the ultimate impact of which remains unclear.

Equity Market Risk — The risk that stock prices will fall over short or extended periods of time.

Exchange-Traded Funds (ETFs) Risk — The risks of owning shares of an ETF generally reflect the risks of owning the underlying securities the ETF is designed to track, although lack of liquidity in an ETF could result in its value being more volatile than the underlying portfolio securities. When the Fund invests in an ETF, in addition to directly bearing the expenses associated with its own operations, it will bear a pro rata portion of the ETF's expenses.

Foreign Investment/Emerging Markets Risk — The risk that non-U.S. securities may be subject to additional risks due to, among other things, political, social and economic developments abroad, currency movements and different legal, regulatory and tax environments. These additional risks may be heightened with respect to emerging market countries because political turmoil and rapid changes in economic conditions are more likely to occur in these countries.

Investment Style Risk — The risk that developed international equity securities may underperform other segments of the equity markets or the equity markets as a whole.

Leverage Risk — The Fund's use of derivatives may result in the Fund's total investment exposure substantially exceeding the value of its portfolio securities and the Fund's investment returns depending substantially on the performance of securities that the Fund may not directly own. The use of leverage can amplify the effects of market volatility on the Fund's share price and may also cause the Fund to liquidate portfolio positions when it would not be advantageous to do so in order to satisfy its obligations. The Fund's use of leverage may result in a heightened risk of investment loss.

Liquidity Risk — The risk that certain securities may be difficult or impossible to sell at the time and the price that the Fund would like. The Fund may have to lower the price of the security, sell other securities instead or forego an investment opportunity, any of which could have a negative effect on Fund management or performance.

Market Risk — The risk that the market value of a security may move up and down, sometimes rapidly and unpredictably. Market risk may affect a single issuer, an industry, a sector or the equity or bond market as a whole.

Participation Notes (P-Notes) Risk — P-Notes are participation interest notes that are issued by banks or broker-dealers and are designed to offer a return linked to a particular underlying equity, debt, currency or market. Investments in P-Notes involve the same risks associated with a direct investment in the underlying foreign companies or foreign securities markets that they seek to replicate. However, there can be no assurance that the trading price of P-Notes will equal the underlying value of the foreign companies or foreign securities markets that they seek to replicate.

Small and Medium Capitalization Risk — The risk that small and medium capitalization companies in which the Fund may invest may be more vulnerable to adverse business or economic events than larger, more established companies. In particular, small and medium capitalization companies may have limited product lines, markets and financial resources and may depend upon a relatively small management group. Therefore, small capitalization and medium capitalization stocks may be more volatile than those of larger companies. Small capitalization and medium capitalization stocks may be traded OTC or listed on an exchange.

Warrants Risk — Warrants are instruments that entitle the holder to buy an equity security at a specific price for a specific period of time. Warrants may be more speculative than other types of investments. The price of a warrant may be more volatile than the price of its underlying security, and a warrant may offer greater potential for capital appreciation as well as capital loss. A warrant ceases to have value if it is not exercised prior to its expiration date.

Investing in the Fund involves risk, and there is no guarantee that the Fund will achieve its investment goal. You could lose money on your investment in the Fund, just as you could with other investments. 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.

Risk Lose Money [Text]

rr_RiskLoseMoney

Investing in the Fund involves risk, and there is no guarantee that the Fund will achieve its investment goal. You could lose money on your investment in the Fund, just as you could with other investments.

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

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.

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

Performance Information

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The bar chart and the performance table below provide some indication of the risks of investing in the Fund by showing changes in the Fund's performance from year to year for the past ten calendar years and by showing how the Fund's average annual returns for 1, 5 and 10 years, and since the Fund's inception, compare with those of a broad measure of market performance. The performance information shown is based on full calendar years. The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future. For current performance information, please call 1-800-DIAL-SEI.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

The bar chart and the performance table below provide some indication of the risks of investing in the Fund by showing changes in the Fund's performance from year to year for the past ten calendar years and by showing how the Fund's average annual returns for 1, 5 and 10 years, and since the Fund's inception, compare with those of a broad measure of market performance.

Performance Availability Phone [Text]

rr_PerformanceAvailabilityPhone

1-800-DIAL-SEI

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future.

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

Best Quarter: 22.94% (06/30/09)
Worst Quarter: -26.25% (09/30/08)

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Best Quarter:

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Jun. 30, 2009

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

22.94%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Worst Quarter:

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Sep. 30, 2008

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(26.25%)

Performance Table Heading

rr_PerformanceTableHeading

Average Annual Total Returns (for the periods ended December 31, 2017)

Index No Deduction for Fees, Expenses, Taxes [Text]

rr_IndexNoDeductionForFeesExpensesTaxes

(reflects no deduction for fees, expenses or taxes)

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes.

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

Your actual after-tax returns will depend on your tax situation and may differ from those shown. After-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts.

Performance Table Explanation after Tax Higher

rr_PerformanceTableExplanationAfterTaxHigher

In the event of negative performance, the Fund's returns after taxes on distributions and sale of Fund shares are calculated assuming that an investor has sufficient capital gains of the same character from other investments to offset any capital losses from the sale of Fund shares. As a result, the Fund's returns after taxes on distributions and sale of Fund shares may exceed the Fund's returns before taxes and/or returns after taxes on distributions.

Performance Table Narrative

rr_PerformanceTableNarrativeTextBlock

After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Your actual after-tax returns will depend on your tax situation and may differ from those shown. After-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts. In the event of negative performance, the Fund's returns after taxes on distributions and sale of Fund shares are calculated assuming that an investor has sufficient capital gains of the same character from other investments to offset any capital losses from the sale of Fund shares. As a result, the Fund's returns after taxes on distributions and sale of Fund shares may exceed the Fund's returns before taxes and/or returns after taxes on distributions.

Class I Prospectus | SIT INTERNATIONAL EQUITY FUND | MSCI EAFE Index Return (reflects no deduction for fees, expenses or taxes)

Risk/Return:

rr_RiskReturnAbstract

Label

rr_AverageAnnualReturnLabel

MSCI EAFE Index Return (reflects no deduction for fees, expenses or taxes)

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

25.03%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

7.90%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

1.94%

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

4.68%

^[1]

Average Annual Returns, Inception Date

rr_AverageAnnualReturnInceptionDate

Dec. 31, 1989

Class I Prospectus | SIT INTERNATIONAL EQUITY FUND | SIT INTERNATIONAL EQUITY FUND - CLASS I

Risk/Return:

rr_RiskReturnAbstract

Management Fees

rr_ManagementFeesOverAssets

0.51%

Distribution (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

none

Other Expenses

rr_OtherExpensesOverAssets

0.89%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

1.40%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

$ 143

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

443

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

766

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

$ 1,680

Annual Return 2008

rr_AnnualReturn2008

(50.47%)

Annual Return 2009

rr_AnnualReturn2009

23.62%

Annual Return 2010

rr_AnnualReturn2010

10.38%

Annual Return 2011

rr_AnnualReturn2011

(13.61%)

Annual Return 2012

rr_AnnualReturn2012

15.76%

Annual Return 2013

rr_AnnualReturn2013

21.08%

Annual Return 2014

rr_AnnualReturn2014

(6.35%)

Annual Return 2015

rr_AnnualReturn2015

1.61%

Annual Return 2016

rr_AnnualReturn2016

(0.76%)

Annual Return 2017

rr_AnnualReturn2017

26.31%

Label

rr_AverageAnnualReturnLabel

Return Before Taxes

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

26.31%

^[2]

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

7.63%

^[2]

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

(0.24%)

^[2]

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

3.65%

^[2]

Average Annual Returns, Inception Date

rr_AverageAnnualReturnInceptionDate

Dec. 20, 1989

Class I Prospectus | SIT INTERNATIONAL EQUITY FUND | SIT INTERNATIONAL EQUITY FUND - CLASS I | After Taxes on Distributions

Risk/Return:

rr_RiskReturnAbstract

Label

rr_AverageAnnualReturnLabel

Return After Taxes on Distributions

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

25.79%

^[2]

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

7.36%

^[2]

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

(0.40%)

^[2]

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

2.83%

^[2]

Class I Prospectus | SIT INTERNATIONAL EQUITY FUND | SIT INTERNATIONAL EQUITY FUND - CLASS I | After Taxes on Distributions and Sale of Fund Shares

Risk/Return:

rr_RiskReturnAbstract

Label

rr_AverageAnnualReturnLabel

Return After Taxes on Distributions and Sale of Fund Shares

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

14.89%

^[2]

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

5.97%

^[2]

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

(0.14%)

^[2]

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

2.76%

^[2]

[1] Index returns are shown from December 31, 1989.

[2] The Fund's Class I Shares commenced operations on January 4, 2002. Therefore, the Fund's average annual total returns for the periods prior to that time are based on the average annual total returns of the Class F Shares, adjusted for the higher expenses of the Class I Shares.

XML

Class Y Prospectus | SIT INTERNATIONAL EQUITY FUND

SIT INTERNATIONAL EQUITY FUND

Investment Goal

Long-term capital appreciation.

Fees and Expenses

The following tables describe the fees and expenses that you may pay if you buy and hold Fund shares.

ANNUAL FUND OPERATING EXPENSES (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses	Class Y Prospectus SIT INTERNATIONAL EQUITY FUND Class Y
Management Fees	0.51%
Distribution (12b-1) Fees	none
Other Expenses	0.39%
Total Annual Fund Operating Expenses	0.90%

EXAMPLE

This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Fund's operating expenses remain the same.

Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Expense Example	1 Year	3 Years	5 Years	10 Years
Class Y Prospectus | SIT INTERNATIONAL EQUITY FUND | Class Y | USD ($)	92	287	498	1,108

PORTFOLIO TURNOVER

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 Fund operating expenses or in the Example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 57% of the average value of its portfolio.

Principal Investment Strategies

Under normal circumstances, the International Equity Fund will invest at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in equity securities. Equity securities may include common stocks, preferred stock, warrants, participation notes and depositary receipts. The Fund will invest primarily in equity securities of issuers of all capitalization ranges that are located in at least three countries other than the U.S. It is expected that at least 40% of the Fund's assets will be invested outside the U.S. The Fund will invest primarily in companies located in developed countries, but may also invest in companies located in emerging markets. Generally, the Fund will invest less than 20% of its assets in emerging markets. Emerging market countries are those countries that are: (i) characterized as developing or emerging by any of the World Bank, the United Nations, the International Finance Corporation, or the European Bank for Reconstruction and Development; (ii) included in an emerging markets index by a recognized index provider; or (iii) countries with similar developing or emerging characteristics as countries classified as emerging market countries pursuant to sub-paragraph (i) and (ii) above, in each case determined at the time of purchase.

The Fund uses a multi-manager approach, relying upon a number of sub-advisers (each, a Sub-Adviser and collectively, the Sub-Advisers) with differing investment philosophies to manage portions of the Fund's portfolio under the general supervision of SEI Investments Management Corporation (SIMC), the Fund's adviser.

The Fund may invest in futures contracts, forward contracts and options for hedging purposes, including seeking to manage the Fund's currency exposure to foreign securities and mitigate the Fund's overall risk.

The Fund may purchase futures contracts or shares of exchange-traded funds (ETFs) to gain exposure to a particular portion of the market while awaiting an opportunity to purchase securities or other instruments directly.

Principal Risks

Credit Risk — The risk that the issuer of a security or the counterparty to a contract will default or otherwise become unable to honor a financial obligation.

Currency Risk — As a result of the Fund's investments in securities denominated in, and/or receiving revenues in, foreign currencies, the Fund will be subject to currency risk. Currency risk is the risk that foreign currencies will decline in value relative to the U.S. dollar or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency hedged. In either event, the dollar value of an investment in the Fund would be adversely affected. Currency exchange rates may fluctuate in response to, among other things, changes in interest rates, intervention (or failure to intervene) by U.S. or foreign governments, central banks or supranational entities, or by the imposition of currency controls or other political developments in the United States or abroad.

Depositary Receipts Risk — Depositary receipts, such as American Depositary Receipts (ADRs), are certificates evidencing ownership of shares of a foreign issuer that are issued by depositary banks and generally trade on an established market. Depositary receipts are subject to many of the risks associated with investing directly in foreign securities, including, among other things, political, social and economic developments abroad, currency movements and different legal, regulatory and tax environments.

Derivatives Risk — The Fund's use of futures contracts, forward contracts and options is subject to market risk, leverage risk, correlation risk and liquidity risk. Leverage risk, liquidity risk and market risk are described below. Many over-the-counter (OTC) derivative instruments will not have liquidity beyond the counterparty to the instrument. Correlation risk is the risk that changes in the value of the derivative may not correlate perfectly with the underlying asset, rate or index. The Fund's use of forward contracts is also subject to credit risk and valuation risk. Valuation risk is the risk that the derivative may be difficult to value and/or valued incorrectly. Credit risk is described above. Each of the above risks could cause the Fund to lose more than the principal amount invested in a derivative instrument. Some derivatives have the potential for unlimited loss, regardless of the size of the Fund's initial investment. The other parties to certain derivative contracts present the same types of credit risk as issuers of fixed income securities. The Fund's use of derivatives may also increase the amount of taxes payable by shareholders. Both U.S. and non-U.S. regulators are in the process of adopting and implementing regulations governing derivatives markets, the ultimate impact of which remains unclear.

Equity Market Risk — The risk that stock prices will fall over short or extended periods of time.

Exchange-Traded Funds (ETFs) Risk — The risks of owning shares of an ETF generally reflect the risks of owning the underlying securities the ETF is designed to track, although lack of liquidity in an ETF could result in its value being more volatile than the underlying portfolio securities. When the Fund invests in an ETF, in addition to directly bearing the expenses associated with its own operations, it will bear a pro rata portion of the ETF's expenses.

Foreign Investment/Emerging Markets Risk — The risk that non-U.S. securities may be subject to additional risks due to, among other things, political, social and economic developments abroad, currency movements and different legal, regulatory and tax environments. These additional risks may be heightened with respect to emerging market countries because political turmoil and rapid changes in economic conditions are more likely to occur in these countries.

Investment Style Risk — The risk that developed international equity securities may underperform other segments of the equity markets or the equity markets as a whole.

Leverage Risk — The Fund's use of derivatives may result in the Fund's total investment exposure substantially exceeding the value of its portfolio securities and the Fund's investment returns depending substantially on the performance of securities that the Fund may not directly own. The use of leverage can amplify the effects of market volatility on the Fund's share price and may also cause the Fund to liquidate portfolio positions when it would not be advantageous to do so in order to satisfy its obligations. The Fund's use of leverage may result in a heightened risk of investment loss.

Liquidity Risk — The risk that certain securities may be difficult or impossible to sell at the time and the price that the Fund would like. The Fund may have to lower the price of the security, sell other securities instead or forego an investment opportunity, any of which could have a negative effect on Fund management or performance.

Market Risk — The risk that the market value of a security may move up and down, sometimes rapidly and unpredictably. Market risk may affect a single issuer, an industry, a sector or the equity or bond market as a whole.

Participation Notes (P-Notes) Risk — P-Notes are participation interest notes that are issued by banks or broker-dealers and are designed to offer a return linked to a particular underlying equity, debt, currency or market. Investments in P-Notes involve the same risks associated with a direct investment in the underlying foreign companies or foreign securities markets that they seek to replicate. However, there can be no assurance that the trading price of P-Notes will equal the underlying value of the foreign companies or foreign securities markets that they seek to replicate.

Small and Medium Capitalization Risk — The risk that small and medium capitalization companies in which the Fund may invest may be more vulnerable to adverse business or economic events than larger, more established companies. In particular, small and medium capitalization companies may have limited product lines, markets and financial resources and may depend upon a relatively small management group. Therefore, small capitalization and medium capitalization stocks may be more volatile than those of larger companies. Small capitalization and medium capitalization stocks may be traded OTC or listed on an exchange.

Warrants Risk — Warrants are instruments that entitle the holder to buy an equity security at a specific price for a specific period of time. Warrants may be more speculative than other types of investments. The price of a warrant may be more volatile than the price of its underlying security, and a warrant may offer greater potential for capital appreciation as well as capital loss. A warrant ceases to have value if it is not exercised prior to its expiration date.

Investing in the Fund involves risk, and there is no guarantee that the Fund will achieve its investment goal. You could lose money on your investment in the Fund, just as you could with other investments. 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.

Performance Information

The bar chart and the performance table below provide some indication of the risks of investing in the Class Y Shares of the Fund by showing changes in the Fund's performance from year to year for the past ten calendar years and by showing how the Fund's average annual returns for 1, 5 and 10 years, and since the Fund's inception, compare with those of a broad measure of market performance. The performance information shown is based on full calendar years. The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future. For current performance information, please call 1-800-DIAL-SEI.

Best Quarter: 22.98% (06/30/09)
Worst Quarter: -26.13% (09/30/08)

Average Annual Total Returns (for the periods ended December 31, 2017)

The Fund's Class Y Shares commenced operations on December 31, 2014. For full calendar years through December 31, 2014, the performance of the Fund's Class F Shares is shown. The Fund's Class F Shares are offered in a separate prospectus. Because Class Y Shares are invested in the same portfolio of securities, returns for Class Y Shares would have been substantially similar to those of Class F Shares, shown here, and would have differed only to the extent that Class Y Shares have lower total annual fund operating expenses than Class F Shares.

After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Your actual after-tax returns will depend on your tax situation and may differ from those shown. After-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts.

Average Annual Returns - Class Y Prospectus - SIT INTERNATIONAL EQUITY FUND	Label	Average Annual Returns, 1 Year		Average Annual Returns, 5 Years		Average Annual Returns, 10 Years		Average Annual Returns, Since Inception		Average Annual Returns, Inception Date
Class Y	Return Before Taxes	26.94%	[1]	8.06%	[1]	0.07%	[1]	3.93%	[1]	Dec. 20, 1989
After Taxes on Distributions | Class Y	Return After Taxes on Distributions	26.11%	[1]	7.50%	[1]	(0.39%)	[1]	3.02%	[1]
After Taxes on Distributions and Sale of Fund Shares | Class Y	Return After Taxes on Distributions and Sale of Fund Shares	15.25%	[1]	6.12%	[1]	(0.12%)	[1]	2.93%	[1]
MSCI EAFE Index Return (reflects no deduction for fees, expenses or taxes)	MSCI EAFE Index Return (reflects no deduction for fees, expenses or taxes)	25.03%		7.90%		1.94%		4.68%	[2]	Dec. 31, 1989

[1] The Fund's Class Y Shares commenced operations on December 31, 2014. For periods prior to December 31, 2014, the performance of the Fund's Class F Shares has been used. Returns for Class Y Shares would have been substantially similar to those of Class F Shares and would have differed only to the extent that Class Y Shares have lower total annual fund operating expenses than Class F Shares.

[2] Index returns are shown from December 31, 1989.

XML

Label

Element

Value

Class Y Prospectus | SIT INTERNATIONAL EQUITY FUND

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

SIT INTERNATIONAL EQUITY FUND

Objective [Heading]

rr_ObjectiveHeading

Investment Goal

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

Long-term capital appreciation.

Expense [Heading]

rr_ExpenseHeading

Fees and Expenses

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

The following tables describe the fees and expenses that you may pay if you buy and hold Fund shares.

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

ANNUAL FUND OPERATING EXPENSES (expenses that you pay each year as a percentage of the value of your investment)

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

PORTFOLIO TURNOVER

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 Fund operating expenses or in the Example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 57% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

57.00%

Expense Example [Heading]

rr_ExpenseExampleHeading

EXAMPLE

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Fund's operating expenses remain the same.

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Strategy [Heading]

rr_StrategyHeading

Principal Investment Strategies

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

Under normal circumstances, the International Equity Fund will invest at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in equity securities. Equity securities may include common stocks, preferred stock, warrants, participation notes and depositary receipts. The Fund will invest primarily in equity securities of issuers of all capitalization ranges that are located in at least three countries other than the U.S. It is expected that at least 40% of the Fund's assets will be invested outside the U.S. The Fund will invest primarily in companies located in developed countries, but may also invest in companies located in emerging markets. Generally, the Fund will invest less than 20% of its assets in emerging markets. Emerging market countries are those countries that are: (i) characterized as developing or emerging by any of the World Bank, the United Nations, the International Finance Corporation, or the European Bank for Reconstruction and Development; (ii) included in an emerging markets index by a recognized index provider; or (iii) countries with similar developing or emerging characteristics as countries classified as emerging market countries pursuant to sub-paragraph (i) and (ii) above, in each case determined at the time of purchase.

The Fund uses a multi-manager approach, relying upon a number of sub-advisers (each, a Sub-Adviser and collectively, the Sub-Advisers) with differing investment philosophies to manage portions of the Fund's portfolio under the general supervision of SEI Investments Management Corporation (SIMC), the Fund's adviser.

The Fund may invest in futures contracts, forward contracts and options for hedging purposes, including seeking to manage the Fund's currency exposure to foreign securities and mitigate the Fund's overall risk.

The Fund may purchase futures contracts or shares of exchange-traded funds (ETFs) to gain exposure to a particular portion of the market while awaiting an opportunity to purchase securities or other instruments directly.

Risk [Heading]

rr_RiskHeading

Principal Risks

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

Credit Risk — The risk that the issuer of a security or the counterparty to a contract will default or otherwise become unable to honor a financial obligation.

Currency Risk — As a result of the Fund's investments in securities denominated in, and/or receiving revenues in, foreign currencies, the Fund will be subject to currency risk. Currency risk is the risk that foreign currencies will decline in value relative to the U.S. dollar or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency hedged. In either event, the dollar value of an investment in the Fund would be adversely affected. Currency exchange rates may fluctuate in response to, among other things, changes in interest rates, intervention (or failure to intervene) by U.S. or foreign governments, central banks or supranational entities, or by the imposition of currency controls or other political developments in the United States or abroad.

Depositary Receipts Risk — Depositary receipts, such as American Depositary Receipts (ADRs), are certificates evidencing ownership of shares of a foreign issuer that are issued by depositary banks and generally trade on an established market. Depositary receipts are subject to many of the risks associated with investing directly in foreign securities, including, among other things, political, social and economic developments abroad, currency movements and different legal, regulatory and tax environments.

Derivatives Risk — The Fund's use of futures contracts, forward contracts and options is subject to market risk, leverage risk, correlation risk and liquidity risk. Leverage risk, liquidity risk and market risk are described below. Many over-the-counter (OTC) derivative instruments will not have liquidity beyond the counterparty to the instrument. Correlation risk is the risk that changes in the value of the derivative may not correlate perfectly with the underlying asset, rate or index. The Fund's use of forward contracts is also subject to credit risk and valuation risk. Valuation risk is the risk that the derivative may be difficult to value and/or valued incorrectly. Credit risk is described above. Each of the above risks could cause the Fund to lose more than the principal amount invested in a derivative instrument. Some derivatives have the potential for unlimited loss, regardless of the size of the Fund's initial investment. The other parties to certain derivative contracts present the same types of credit risk as issuers of fixed income securities. The Fund's use of derivatives may also increase the amount of taxes payable by shareholders. Both U.S. and non-U.S. regulators are in the process of adopting and implementing regulations governing derivatives markets, the ultimate impact of which remains unclear.

Equity Market Risk — The risk that stock prices will fall over short or extended periods of time.

Exchange-Traded Funds (ETFs) Risk — The risks of owning shares of an ETF generally reflect the risks of owning the underlying securities the ETF is designed to track, although lack of liquidity in an ETF could result in its value being more volatile than the underlying portfolio securities. When the Fund invests in an ETF, in addition to directly bearing the expenses associated with its own operations, it will bear a pro rata portion of the ETF's expenses.

Foreign Investment/Emerging Markets Risk — The risk that non-U.S. securities may be subject to additional risks due to, among other things, political, social and economic developments abroad, currency movements and different legal, regulatory and tax environments. These additional risks may be heightened with respect to emerging market countries because political turmoil and rapid changes in economic conditions are more likely to occur in these countries.

Investment Style Risk — The risk that developed international equity securities may underperform other segments of the equity markets or the equity markets as a whole.

Leverage Risk — The Fund's use of derivatives may result in the Fund's total investment exposure substantially exceeding the value of its portfolio securities and the Fund's investment returns depending substantially on the performance of securities that the Fund may not directly own. The use of leverage can amplify the effects of market volatility on the Fund's share price and may also cause the Fund to liquidate portfolio positions when it would not be advantageous to do so in order to satisfy its obligations. The Fund's use of leverage may result in a heightened risk of investment loss.

Liquidity Risk — The risk that certain securities may be difficult or impossible to sell at the time and the price that the Fund would like. The Fund may have to lower the price of the security, sell other securities instead or forego an investment opportunity, any of which could have a negative effect on Fund management or performance.

Market Risk — The risk that the market value of a security may move up and down, sometimes rapidly and unpredictably. Market risk may affect a single issuer, an industry, a sector or the equity or bond market as a whole.

Participation Notes (P-Notes) Risk — P-Notes are participation interest notes that are issued by banks or broker-dealers and are designed to offer a return linked to a particular underlying equity, debt, currency or market. Investments in P-Notes involve the same risks associated with a direct investment in the underlying foreign companies or foreign securities markets that they seek to replicate. However, there can be no assurance that the trading price of P-Notes will equal the underlying value of the foreign companies or foreign securities markets that they seek to replicate.

Small and Medium Capitalization Risk — The risk that small and medium capitalization companies in which the Fund may invest may be more vulnerable to adverse business or economic events than larger, more established companies. In particular, small and medium capitalization companies may have limited product lines, markets and financial resources and may depend upon a relatively small management group. Therefore, small capitalization and medium capitalization stocks may be more volatile than those of larger companies. Small capitalization and medium capitalization stocks may be traded OTC or listed on an exchange.

Warrants Risk — Warrants are instruments that entitle the holder to buy an equity security at a specific price for a specific period of time. Warrants may be more speculative than other types of investments. The price of a warrant may be more volatile than the price of its underlying security, and a warrant may offer greater potential for capital appreciation as well as capital loss. A warrant ceases to have value if it is not exercised prior to its expiration date.

Investing in the Fund involves risk, and there is no guarantee that the Fund will achieve its investment goal. You could lose money on your investment in the Fund, just as you could with other investments. 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.

Risk Lose Money [Text]

rr_RiskLoseMoney

Investing in the Fund involves risk, and there is no guarantee that the Fund will achieve its investment goal. You could lose money on your investment in the Fund, just as you could with other investments.

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

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.

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

Performance Information

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The bar chart and the performance table below provide some indication of the risks of investing in the Class Y Shares of the Fund by showing changes in the Fund's performance from year to year for the past ten calendar years and by showing how the Fund's average annual returns for 1, 5 and 10 years, and since the Fund's inception, compare with those of a broad measure of market performance. The performance information shown is based on full calendar years. The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future. For current performance information, please call 1-800-DIAL-SEI.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

The bar chart and the performance table below provide some indication of the risks of investing in the Class Y Shares of the Fund by showing changes in the Fund's performance from year to year for the past ten calendar years and by showing how the Fund's average annual returns for 1, 5 and 10 years, and since the Fund's inception, compare with those of a broad measure of market performance.

Performance Availability Phone [Text]

rr_PerformanceAvailabilityPhone

1-800-DIAL-SEI

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future.

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

Best Quarter: 22.98% (06/30/09)
Worst Quarter: -26.13% (09/30/08)

Bar Chart, Returns for Class Not Offered in Prospectus [Text]

rr_BarChartReturnsForClassNotOfferedInProspectus

The Fund's Class F Shares are offered in a separate prospectus.

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Best Quarter:

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Jun. 30, 2009

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

22.98%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Worst Quarter:

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Sep. 30, 2008

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(26.13%)

Performance Table Heading

rr_PerformanceTableHeading

Average Annual Total Returns (for the periods ended December 31, 2017)

Index No Deduction for Fees, Expenses, Taxes [Text]

rr_IndexNoDeductionForFeesExpensesTaxes

(reflects no deduction for fees, expenses or taxes)

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes.

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

Your actual after-tax returns will depend on your tax situation and may differ from those shown. After-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts.

Performance Table Narrative

rr_PerformanceTableNarrativeTextBlock

The Fund's Class Y Shares commenced operations on December 31, 2014. For full calendar years through December 31, 2014, the performance of the Fund's Class F Shares is shown. The Fund's Class F Shares are offered in a separate prospectus. Because Class Y Shares are invested in the same portfolio of securities, returns for Class Y Shares would have been substantially similar to those of Class F Shares, shown here, and would have differed only to the extent that Class Y Shares have lower total annual fund operating expenses than Class F Shares.

After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Your actual after-tax returns will depend on your tax situation and may differ from those shown. After-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts.

Class Y Prospectus | SIT INTERNATIONAL EQUITY FUND | MSCI EAFE Index Return (reflects no deduction for fees, expenses or taxes)

Risk/Return:

rr_RiskReturnAbstract

Label

rr_AverageAnnualReturnLabel

MSCI EAFE Index Return (reflects no deduction for fees, expenses or taxes)

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

25.03%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

7.90%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

1.94%

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

4.68%

^[1]

Average Annual Returns, Inception Date

rr_AverageAnnualReturnInceptionDate

Dec. 31, 1989

Class Y Prospectus | SIT INTERNATIONAL EQUITY FUND | Class Y

Risk/Return:

rr_RiskReturnAbstract

Management Fees

rr_ManagementFeesOverAssets

0.51%

Distribution (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

none

Other Expenses

rr_OtherExpensesOverAssets

0.39%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

0.90%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

$ 92

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

287

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

498

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

$ 1,108

Annual Return 2008

rr_AnnualReturn2008

(50.39%)

Annual Return 2009

rr_AnnualReturn2009

24.00%

Annual Return 2010

rr_AnnualReturn2010

10.74%

Annual Return 2011

rr_AnnualReturn2011

(13.52%)

Annual Return 2012

rr_AnnualReturn2012

16.07%

Annual Return 2013

rr_AnnualReturn2013

21.38%

Annual Return 2014

rr_AnnualReturn2014

(6.07%)

Annual Return 2015

rr_AnnualReturn2015

2.11%

Annual Return 2016

rr_AnnualReturn2016

(0.31%)

Annual Return 2017

rr_AnnualReturn2017

26.94%

Label

rr_AverageAnnualReturnLabel

Return Before Taxes

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

26.94%

^[2]

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

8.06%

^[2]

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

0.07%

^[2]

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

3.93%

^[2]

Average Annual Returns, Inception Date

rr_AverageAnnualReturnInceptionDate

Dec. 20, 1989

Class Y Prospectus | SIT INTERNATIONAL EQUITY FUND | Class Y | After Taxes on Distributions

Risk/Return:

rr_RiskReturnAbstract

Label

rr_AverageAnnualReturnLabel

Return After Taxes on Distributions

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

26.11%

^[2]

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

7.50%

^[2]

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

(0.39%)

^[2]

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

3.02%

^[2]

Class Y Prospectus | SIT INTERNATIONAL EQUITY FUND | Class Y | After Taxes on Distributions and Sale of Fund Shares

Risk/Return:

rr_RiskReturnAbstract

Label

rr_AverageAnnualReturnLabel

Return After Taxes on Distributions and Sale of Fund Shares

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

15.25%

^[2]

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

6.12%

^[2]

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

(0.12%)

^[2]

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

2.93%

^[2]

[1] Index returns are shown from December 31, 1989.

[2] The Fund's Class Y Shares commenced operations on December 31, 2014. For periods prior to December 31, 2014, the performance of the Fund's Class F Shares has been used. Returns for Class Y Shares would have been substantially similar to those of Class F Shares and would have differed only to the extent that Class Y Shares have lower total annual fund operating expenses than Class F Shares.

XML

Class Y Prospectus | SIT EMERGING MARKETS EQUITY FUND

SIT EMERGING MARKETS EQUITY FUND

Investment Goal

Capital appreciation.

Fees and Expenses

The following tables describe the fees and expenses that you may pay if you buy and hold Fund shares.

ANNUAL FUND OPERATING EXPENSES (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses	Class Y Prospectus SIT EMERGING MARKETS EQUITY FUND Class Y
Management Fees	1.05%
Distribution (12b-1) Fees	none
Other Expenses	0.52%
Total Annual Fund Operating Expenses	1.57%
Fee Waivers and Expense Reimbursements	(0.10%)
Total Annual Fund Operating Expenses Less Fee Waivers and Expense Reimbursements	1.47%	[1]

EXAMPLE

This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Fund's operating expenses remain the same.

Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Expense Example	1 Year	3 Years	5 Years	10 Years
Class Y Prospectus | SIT EMERGING MARKETS EQUITY FUND | Class Y | USD ($)	150	486	846	1,859

PORTFOLIO TURNOVER

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 Fund operating expenses or in the Example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 66% of the average value of its portfolio.

Principal Investment Strategies

Under normal circumstances, the Emerging Markets Equity Fund will invest at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in equity securities of emerging market issuers. Equity securities may include common stocks, preferred stock, warrants, participation notes and depositary receipts. The Fund normally maintains investments in at least six emerging market countries and does not invest more than 35% of its total assets in any one emerging market country. Emerging market countries are those countries that are: (i) characterized as developing or emerging by any of the World Bank, the United Nations, the International Finance Corporation, or the European Bank for Reconstruction and Development; (ii) included in an emerging markets index by a recognized index provider; or (iii) countries with similar developing or emerging characteristics as countries classified as emerging market countries pursuant to sub-paragraph (i) and (ii) above, in each case determined at the time of purchase.

The Fund uses a multi-manager approach, relying upon a number of sub-advisers (each, a Sub-Adviser and collectively, the Sub-Advisers) with differing investment philosophies to manage portions of the Fund's portfolio under the general supervision of SEI Investments Management Corporation (SIMC), the Fund's adviser.

The Fund may invest in swaps based on a single security or an index of securities, futures contracts, forward contracts and options to synthetically obtain exposure to securities or baskets of securities or for hedging purposes, including seeking to manage the Fund's currency exposure to foreign securities and mitigate the Fund's overall risk. Swaps may be used to obtain exposure to different foreign equity markets.

The Fund may purchase futures contracts or shares of exchange-traded funds (ETFs) to gain exposure to a particular portion of the market while awaiting an opportunity to purchase securities or other instruments directly. The Fund may also invest a portion of its assets in securities of companies located in developed foreign countries and securities of small capitalization companies.

Principal Risks

Credit Risk — The risk that the issuer of a security or the counterparty to a contract will default or otherwise become unable to honor a financial obligation.

Currency Risk — As a result of the Fund's investments in securities denominated in, and/or receiving revenues in, foreign currencies, the Fund will be subject to currency risk. Currency risk is the risk that foreign currencies will decline in value relative to the U.S. dollar or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency hedged. In either event, the dollar value of an investment in the Fund would be adversely affected. Currency exchange rates may fluctuate in response to, among other things, changes in interest rates, intervention (or failure to intervene) by U.S. or foreign governments, central banks or supranational entities, or by the imposition of currency controls or other political developments in the United States or abroad.

Depositary Receipts Risk — Depositary receipts, such as American Depositary Receipts (ADRs), are certificates evidencing ownership of shares of a foreign issuer that are issued by depositary banks and generally trade on an established market. Depositary receipts are subject to many of the risks associated with investing directly in foreign securities, including, among other things, political, social and economic developments abroad, currency movements and different legal, regulatory and tax environments.

Derivatives Risk — The Fund's use of futures contracts, forward contracts, options and swaps is subject to market risk, leverage risk, correlation risk and liquidity risk. Leverage risk, liquidity risk and market risk are described below. Many over-the-counter (OTC) derivative instruments will not have liquidity beyond the counterparty to the instrument. Correlation risk is the risk that changes in the value of the derivative may not correlate perfectly with the underlying asset, rate or index. The Fund's use of forward contracts and swap agreements is also subject to credit risk and valuation risk. Valuation risk is the risk that the derivative may be difficult to value and/or valued incorrectly. Credit risk is described above. Each of the above risks could cause the Fund to lose more than the principal amount invested in a derivative instrument. Some derivatives have the potential for unlimited loss, regardless of the size of the Fund's initial investment. The other parties to certain derivative contracts present the same types of credit risk as issuers of fixed income securities. The Fund's use of derivatives may also increase the amount of taxes payable by shareholders. Both U.S. and non-U.S. regulators are in the process of adopting and implementing regulations governing derivatives markets, the ultimate impact of which remains unclear.

Equity Market Risk — The risk that stock prices will fall over short or extended periods of time.

Exchange-Traded Funds (ETFs) Risk — The risks of owning shares of an ETF generally reflect the risks of owning the underlying securities the ETF is designed to track, although lack of liquidity in an ETF could result in its value being more volatile than the underlying portfolio securities. When the Fund invests in an ETF, in addition to directly bearing the expenses associated with its own operations, it will bear a pro rata portion of the ETF's expenses.

Foreign Investment/Emerging Markets Risk — The risk that non-U.S. securities may be subject to additional risks due to, among other things, political, social and economic developments abroad, currency movements and different legal, regulatory and tax environments. These additional risks may be heightened with respect to emerging market countries because political turmoil and rapid changes in economic conditions are more likely to occur in these countries.

Investment Style Risk — The risk that emerging market equity securities may underperform other segments of the equity markets or the equity markets as a whole.

Leverage Risk — The Fund's use of derivatives may result in the Fund's total investment exposure substantially exceeding the value of its portfolio securities and the Fund's investment returns depending substantially on the performance of securities that the Fund may not directly own. The use of leverage can amplify the effects of market volatility on the Fund's share price and may also cause the Fund to liquidate portfolio positions when it would not be advantageous to do so in order to satisfy its obligations. The Fund's use of leverage may result in a heightened risk of investment loss.

Liquidity Risk — The risk that certain securities may be difficult or impossible to sell at the time and the price that the Fund would like. The Fund may have to lower the price of the security, sell other securities instead or forego an investment opportunity, any of which could have a negative effect on Fund management or performance.

Market Risk — The risk that the market value of a security may move up and down, sometimes rapidly and unpredictably. Market risk may affect a single issuer, an industry, a sector or the equity or bond market as a whole.

Participation Notes (P-Notes) Risk — P-Notes are participation interest notes that are issued by banks or broker-dealers and are designed to offer a return linked to a particular underlying equity, debt, currency or market. Investments in P-Notes involve the same risks associated with a direct investment in the underlying foreign companies or foreign securities markets that they seek to replicate. However, there can be no assurance that the trading price of P-Notes will equal the underlying value of the foreign companies or foreign securities markets that they seek to replicate.

Small and Medium Capitalization Risk — The risk that small and medium capitalization companies in which the Fund may invest may be more vulnerable to adverse business or economic events than larger, more established companies. In particular, small and medium capitalization companies may have limited product lines, markets and financial resources and may depend upon a relatively small management group. Therefore, small capitalization and medium capitalization stocks may be more volatile than those of larger companies. Small capitalization and medium capitalization stocks may be traded over the counter or listed on an exchange.

Warrants Risk — Warrants are instruments that entitle the holder to buy an equity security at a specific price for a specific period of time. Warrants may be more speculative than other types of investments. The price of a warrant may be more volatile than the price of its underlying security, and a warrant may offer greater potential for capital appreciation as well as capital loss. A warrant ceases to have value if it is not exercised prior to its expiration date.

Investing in the Fund involves risk, and there is no guarantee that the Fund will achieve its investment goal. You could lose money on your investment in the Fund, just as you could with other investments. 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.

Performance Information

The bar chart and the performance table below provide some indication of the risks of investing in the Class Y Shares of the Fund by showing changes in the Fund's performance from year to year for the past ten calendar years and by showing how the Fund's average annual returns for 1, 5 and 10 years, and since the Fund's inception, compare with those of a broad measure of market performance. The performance information shown is based on full calendar years. The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future. For current performance information, please call 1-800-DIAL-SEI.

Best Quarter: 34.40% (06/30/09)
Worst Quarter: -27.79% (12/31/08)

Average Annual Total Returns (for the periods ended December 31, 2017)

The Fund's Class Y Shares commenced operations on December 31, 2014. For full calendar years through December 31, 2014, the performance of the Fund's Class F Shares is shown. The Fund's Class F Shares are offered in a separate prospectus. Because Class Y Shares are invested in the same portfolio of securities, returns for Class Y Shares would have been substantially similar to those of Class F Shares, shown here, and would have differed only to the extent that Class Y Shares have lower total annual fund operating expenses than Class F Shares.

After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Your actual after-tax returns will depend on your tax situation and may differ from those shown. After-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts.

Average Annual Returns - Class Y Prospectus - SIT EMERGING MARKETS EQUITY FUND	Label	Average Annual Returns, 1 Year		Average Annual Returns, 5 Years		Average Annual Returns, 10 Years		Average Annual Returns, Since Inception		Average Annual Returns, Inception Date
Class Y	Return Before Taxes	37.58%	[1]	4.72%	[1]	0.98%	[1]	5.15%	[1]	Jan. 17, 1995
After Taxes on Distributions | Class Y	Return After Taxes on Distributions	36.69%	[1]	4.49%	[1]	0.46%	[1]	4.55%	[1]
After Taxes on Distributions and Sale of Fund Shares | Class Y	Return After Taxes on Distributions and Sale of Fund Shares	21.26%	[1]	3.65%	[1]	0.70%	[1]	4.36%	[1]
MSCI Emerging Markets Index Return (reflects no deduction for fees, expenses or taxes)	MSCI Emerging Markets Index Return (reflects no deduction for fees, expenses or taxes)	37.75%		4.73%		2.02%		7.00%	[2]	Jan. 31, 1995

[1] Renewed as of January 31, 2018, SIMC, the Fund's investment adviser, has contractually agreed to waive its management fee as necessary to keep the management fee paid by the Fund during its fiscal year from exceeding 0.95%. This fee waiver agreement shall remain in effect until January 31, 2019 and, unless earlier terminated, shall be automatically renewed for successive one-year periods thereafter. The agreement may be amended or terminated only with the consent of the Board of Trustees.

[1] The Fund's Class Y Shares commenced operations on December 31, 2014. For periods prior to December 31, 2014, the performance of the Fund's Class F Shares has been used. Returns for Class Y Shares would have been substantially similar to those of Class F Shares and would have differed only to the extent that Class Y Shares have lower total annual fund operating expenses than Class F Shares.

[2] Index returns are shown from January 31, 1995.

XML

Label

Element

Value

Class Y Prospectus | SIT EMERGING MARKETS EQUITY FUND

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

SIT EMERGING MARKETS EQUITY FUND

Objective [Heading]

rr_ObjectiveHeading

Investment Goal

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

Capital appreciation.

Expense [Heading]

rr_ExpenseHeading

Fees and Expenses

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

The following tables describe the fees and expenses that you may pay if you buy and hold Fund shares.

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

ANNUAL FUND OPERATING EXPENSES (expenses that you pay each year as a percentage of the value of your investment)

Fee Waiver or Reimbursement over Assets, Date of Termination

rr_FeeWaiverOrReimbursementOverAssetsDateOfTermination

Jan. 31, 2019

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

PORTFOLIO TURNOVER

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 Fund operating expenses or in the Example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 66% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

66.00%

Expense Example [Heading]

rr_ExpenseExampleHeading

EXAMPLE

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Fund's operating expenses remain the same.

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Strategy [Heading]

rr_StrategyHeading

Principal Investment Strategies

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

Under normal circumstances, the Emerging Markets Equity Fund will invest at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in equity securities of emerging market issuers. Equity securities may include common stocks, preferred stock, warrants, participation notes and depositary receipts. The Fund normally maintains investments in at least six emerging market countries and does not invest more than 35% of its total assets in any one emerging market country. Emerging market countries are those countries that are: (i) characterized as developing or emerging by any of the World Bank, the United Nations, the International Finance Corporation, or the European Bank for Reconstruction and Development; (ii) included in an emerging markets index by a recognized index provider; or (iii) countries with similar developing or emerging characteristics as countries classified as emerging market countries pursuant to sub-paragraph (i) and (ii) above, in each case determined at the time of purchase.

The Fund uses a multi-manager approach, relying upon a number of sub-advisers (each, a Sub-Adviser and collectively, the Sub-Advisers) with differing investment philosophies to manage portions of the Fund's portfolio under the general supervision of SEI Investments Management Corporation (SIMC), the Fund's adviser.

The Fund may invest in swaps based on a single security or an index of securities, futures contracts, forward contracts and options to synthetically obtain exposure to securities or baskets of securities or for hedging purposes, including seeking to manage the Fund's currency exposure to foreign securities and mitigate the Fund's overall risk. Swaps may be used to obtain exposure to different foreign equity markets.

The Fund may purchase futures contracts or shares of exchange-traded funds (ETFs) to gain exposure to a particular portion of the market while awaiting an opportunity to purchase securities or other instruments directly. The Fund may also invest a portion of its assets in securities of companies located in developed foreign countries and securities of small capitalization companies.

Risk [Heading]

rr_RiskHeading

Principal Risks

Risk Narrative [Text Block]

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Credit Risk — The risk that the issuer of a security or the counterparty to a contract will default or otherwise become unable to honor a financial obligation.

Currency Risk — As a result of the Fund's investments in securities denominated in, and/or receiving revenues in, foreign currencies, the Fund will be subject to currency risk. Currency risk is the risk that foreign currencies will decline in value relative to the U.S. dollar or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency hedged. In either event, the dollar value of an investment in the Fund would be adversely affected. Currency exchange rates may fluctuate in response to, among other things, changes in interest rates, intervention (or failure to intervene) by U.S. or foreign governments, central banks or supranational entities, or by the imposition of currency controls or other political developments in the United States or abroad.

Depositary Receipts Risk — Depositary receipts, such as American Depositary Receipts (ADRs), are certificates evidencing ownership of shares of a foreign issuer that are issued by depositary banks and generally trade on an established market. Depositary receipts are subject to many of the risks associated with investing directly in foreign securities, including, among other things, political, social and economic developments abroad, currency movements and different legal, regulatory and tax environments.

Derivatives Risk — The Fund's use of futures contracts, forward contracts, options and swaps is subject to market risk, leverage risk, correlation risk and liquidity risk. Leverage risk, liquidity risk and market risk are described below. Many over-the-counter (OTC) derivative instruments will not have liquidity beyond the counterparty to the instrument. Correlation risk is the risk that changes in the value of the derivative may not correlate perfectly with the underlying asset, rate or index. The Fund's use of forward contracts and swap agreements is also subject to credit risk and valuation risk. Valuation risk is the risk that the derivative may be difficult to value and/or valued incorrectly. Credit risk is described above. Each of the above risks could cause the Fund to lose more than the principal amount invested in a derivative instrument. Some derivatives have the potential for unlimited loss, regardless of the size of the Fund's initial investment. The other parties to certain derivative contracts present the same types of credit risk as issuers of fixed income securities. The Fund's use of derivatives may also increase the amount of taxes payable by shareholders. Both U.S. and non-U.S. regulators are in the process of adopting and implementing regulations governing derivatives markets, the ultimate impact of which remains unclear.

Equity Market Risk — The risk that stock prices will fall over short or extended periods of time.

Exchange-Traded Funds (ETFs) Risk — The risks of owning shares of an ETF generally reflect the risks of owning the underlying securities the ETF is designed to track, although lack of liquidity in an ETF could result in its value being more volatile than the underlying portfolio securities. When the Fund invests in an ETF, in addition to directly bearing the expenses associated with its own operations, it will bear a pro rata portion of the ETF's expenses.

Foreign Investment/Emerging Markets Risk — The risk that non-U.S. securities may be subject to additional risks due to, among other things, political, social and economic developments abroad, currency movements and different legal, regulatory and tax environments. These additional risks may be heightened with respect to emerging market countries because political turmoil and rapid changes in economic conditions are more likely to occur in these countries.

Investment Style Risk — The risk that emerging market equity securities may underperform other segments of the equity markets or the equity markets as a whole.

Leverage Risk — The Fund's use of derivatives may result in the Fund's total investment exposure substantially exceeding the value of its portfolio securities and the Fund's investment returns depending substantially on the performance of securities that the Fund may not directly own. The use of leverage can amplify the effects of market volatility on the Fund's share price and may also cause the Fund to liquidate portfolio positions when it would not be advantageous to do so in order to satisfy its obligations. The Fund's use of leverage may result in a heightened risk of investment loss.

Liquidity Risk — The risk that certain securities may be difficult or impossible to sell at the time and the price that the Fund would like. The Fund may have to lower the price of the security, sell other securities instead or forego an investment opportunity, any of which could have a negative effect on Fund management or performance.

Market Risk — The risk that the market value of a security may move up and down, sometimes rapidly and unpredictably. Market risk may affect a single issuer, an industry, a sector or the equity or bond market as a whole.

Participation Notes (P-Notes) Risk — P-Notes are participation interest notes that are issued by banks or broker-dealers and are designed to offer a return linked to a particular underlying equity, debt, currency or market. Investments in P-Notes involve the same risks associated with a direct investment in the underlying foreign companies or foreign securities markets that they seek to replicate. However, there can be no assurance that the trading price of P-Notes will equal the underlying value of the foreign companies or foreign securities markets that they seek to replicate.

Small and Medium Capitalization Risk — The risk that small and medium capitalization companies in which the Fund may invest may be more vulnerable to adverse business or economic events than larger, more established companies. In particular, small and medium capitalization companies may have limited product lines, markets and financial resources and may depend upon a relatively small management group. Therefore, small capitalization and medium capitalization stocks may be more volatile than those of larger companies. Small capitalization and medium capitalization stocks may be traded over the counter or listed on an exchange.

Warrants Risk — Warrants are instruments that entitle the holder to buy an equity security at a specific price for a specific period of time. Warrants may be more speculative than other types of investments. The price of a warrant may be more volatile than the price of its underlying security, and a warrant may offer greater potential for capital appreciation as well as capital loss. A warrant ceases to have value if it is not exercised prior to its expiration date.

Investing in the Fund involves risk, and there is no guarantee that the Fund will achieve its investment goal. You could lose money on your investment in the Fund, just as you could with other investments. 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.

Risk Lose Money [Text]

rr_RiskLoseMoney

Investing in the Fund involves risk, and there is no guarantee that the Fund will achieve its investment goal. You could lose money on your investment in the Fund, just as you could with other investments.

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

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.

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

Performance Information

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The bar chart and the performance table below provide some indication of the risks of investing in the Class Y Shares of the Fund by showing changes in the Fund's performance from year to year for the past ten calendar years and by showing how the Fund's average annual returns for 1, 5 and 10 years, and since the Fund's inception, compare with those of a broad measure of market performance. The performance information shown is based on full calendar years. The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future. For current performance information, please call 1-800-DIAL-SEI.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

The bar chart and the performance table below provide some indication of the risks of investing in the Class Y Shares of the Fund by showing changes in the Fund's performance from year to year for the past ten calendar years and by showing how the Fund's average annual returns for 1, 5 and 10 years, and since the Fund's inception, compare with those of a broad measure of market performance.

Performance Availability Phone [Text]

rr_PerformanceAvailabilityPhone

1-800-DIAL-SEI

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future.

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

Best Quarter: 34.40% (06/30/09)
Worst Quarter: -27.79% (12/31/08)

Bar Chart, Returns for Class Not Offered in Prospectus [Text]

rr_BarChartReturnsForClassNotOfferedInProspectus

The Fund's Class F Shares are offered in a separate prospectus.

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Best Quarter:

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Jun. 30, 2009

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

34.40%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Worst Quarter:

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Dec. 31, 2008

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(27.79%)

Performance Table Heading

rr_PerformanceTableHeading

Average Annual Total Returns (for the periods ended December 31, 2017)

Index No Deduction for Fees, Expenses, Taxes [Text]

rr_IndexNoDeductionForFeesExpensesTaxes

(reflects no deduction for fees, expenses or taxes)

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes.

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

Your actual after-tax returns will depend on your tax situation and may differ from those shown. After-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts.

Performance Table Narrative

rr_PerformanceTableNarrativeTextBlock

The Fund's Class Y Shares commenced operations on December 31, 2014. For full calendar years through December 31, 2014, the performance of the Fund's Class F Shares is shown. The Fund's Class F Shares are offered in a separate prospectus. Because Class Y Shares are invested in the same portfolio of securities, returns for Class Y Shares would have been substantially similar to those of Class F Shares, shown here, and would have differed only to the extent that Class Y Shares have lower total annual fund operating expenses than Class F Shares.

After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Your actual after-tax returns will depend on your tax situation and may differ from those shown. After-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts.

Class Y Prospectus | SIT EMERGING MARKETS EQUITY FUND | MSCI Emerging Markets Index Return (reflects no deduction for fees, expenses or taxes)

Risk/Return:

rr_RiskReturnAbstract

Label

rr_AverageAnnualReturnLabel

MSCI Emerging Markets Index Return (reflects no deduction for fees, expenses or taxes)

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

37.75%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

4.73%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

2.02%

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

7.00%

^[1]

Average Annual Returns, Inception Date

rr_AverageAnnualReturnInceptionDate

Jan. 31, 1995

Class Y Prospectus | SIT EMERGING MARKETS EQUITY FUND | Class Y

Risk/Return:

rr_RiskReturnAbstract

Management Fees

rr_ManagementFeesOverAssets

1.05%

Distribution (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

none

Other Expenses

rr_OtherExpensesOverAssets

0.52%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

1.57%

Fee Waivers and Expense Reimbursements

rr_FeeWaiverOrReimbursementOverAssets

(0.10%)

Total Annual Fund Operating Expenses Less Fee Waivers and Expense Reimbursements

rr_NetExpensesOverAssets

1.47%

^[2]

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

$ 150

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

486

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

846

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

$ 1,859

Annual Return 2008

rr_AnnualReturn2008

(52.68%)

Annual Return 2009

rr_AnnualReturn2009

75.07%

Annual Return 2010

rr_AnnualReturn2010

17.70%

Annual Return 2011

rr_AnnualReturn2011

(23.32%)

Annual Return 2012

rr_AnnualReturn2012

17.10%

Annual Return 2013

rr_AnnualReturn2013

(0.26%)

Annual Return 2014

rr_AnnualReturn2014

(5.10%)

Annual Return 2015

rr_AnnualReturn2015

(14.25%)

Annual Return 2016

rr_AnnualReturn2016

12.77%

Annual Return 2017

rr_AnnualReturn2017

37.58%

Label

rr_AverageAnnualReturnLabel

Return Before Taxes

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

37.58%

^[3]

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

4.72%

^[3]

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

0.98%

^[3]

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

5.15%

^[3]

Average Annual Returns, Inception Date

rr_AverageAnnualReturnInceptionDate

Jan. 17, 1995

Class Y Prospectus | SIT EMERGING MARKETS EQUITY FUND | Class Y | After Taxes on Distributions

Risk/Return:

rr_RiskReturnAbstract

Label

rr_AverageAnnualReturnLabel

Return After Taxes on Distributions

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

36.69%

^[3]

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

4.49%

^[3]

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

0.46%

^[3]

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

4.55%

^[3]

Class Y Prospectus | SIT EMERGING MARKETS EQUITY FUND | Class Y | After Taxes on Distributions and Sale of Fund Shares

Risk/Return:

rr_RiskReturnAbstract

Label

rr_AverageAnnualReturnLabel

Return After Taxes on Distributions and Sale of Fund Shares

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

21.26%

^[3]

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

3.65%

^[3]

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

0.70%

^[3]

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

4.36%

^[3]

[1] Index returns are shown from January 31, 1995.

[2] Renewed as of January 31, 2018, SIMC, the Fund's investment adviser, has contractually agreed to waive its management fee as necessary to keep the management fee paid by the Fund during its fiscal year from exceeding 0.95%. This fee waiver agreement shall remain in effect until January 31, 2019 and, unless earlier terminated, shall be automatically renewed for successive one-year periods thereafter. The agreement may be amended or terminated only with the consent of the Board of Trustees.

[3] The Fund's Class Y Shares commenced operations on December 31, 2014. For periods prior to December 31, 2014, the performance of the Fund's Class F Shares has been used. Returns for Class Y Shares would have been substantially similar to those of Class F Shares and would have differed only to the extent that Class Y Shares have lower total annual fund operating expenses than Class F Shares.

XML

Class Y Prospectus | SIT INTERNATIONAL FIXED INCOME FUND

SIT INTERNATIONAL FIXED INCOME FUND

Investment Goal

Capital appreciation and current income.

Fees and Expenses

The following tables describe the fees and expenses that you may pay if you buy and hold Fund shares.

ANNUAL FUND OPERATING EXPENSES (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses	Class Y Prospectus SIT INTERNATIONAL FIXED INCOME FUND Class Y
Management Fees	0.30%
Distribution (12b-1) Fees	none
Other Expenses	0.53%
Total Annual Fund Operating Expenses	0.83%

EXAMPLE

This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Fund's operating expenses remain the same.

Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Expense Example	1 Year	3 Years	5 Years	10 Years
Class Y Prospectus | SIT INTERNATIONAL FIXED INCOME FUND | Class Y | USD ($)	85	265	460	1,025

PORTFOLIO TURNOVER

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 Fund operating expenses or in the Example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 113% of the average value of its portfolio.

Principal Investment Strategies

Under normal circumstances, the International Fixed Income Fund will invest at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in fixed income securities. The Fund will invest primarily in investment grade foreign government and corporate fixed income securities, as well as foreign mortgage-backed and/or asset-backed fixed income securities, of issuers located in at least three countries other than the U.S. (including, to a lesser extent, emerging market countries). It is expected that at least 40% of the Fund's assets will be invested in non-U.S. securities. Other fixed income securities in which the Fund may invest include: (i) securities issued or guaranteed by the U.S. Government and its agencies and instrumentalities and obligations of U.S. commercial banks, such as certificates of deposit, time deposits, bankers' acceptances and bank notes; (ii) U.S. corporate debt securities and mortgage-backed and asset-backed securities; and (iii) obligations of supranational entities.

The Fund uses a multi-manager approach, relying upon a number of sub-advisers (each, a Sub-Adviser and collectively, the Sub-Advisers) with differing investment philosophies to manage portions of the Fund's portfolio under the general supervision of SEI Investments Management Corporation (SIMC), the Fund's adviser. In selecting investments for the Fund, the Sub-Advisers choose securities issued by corporations and governments located in various countries, looking for opportunities to achieve capital appreciation and gain, as well as current income. There are no restrictions on the Fund's average portfolio maturity or on the maturity of any specific security.

The Sub-Advisers may seek to enhance the Fund's return by actively managing the Fund's foreign currency exposure. In managing the Fund's currency exposure, the Sub-Advisers buy and sell currencies (i.e., take long or short positions) using derivatives, principally futures, foreign currency forward contracts and currency swaps. The Fund may take long and short positions in foreign currencies in excess of the value of the Fund's assets denominated in a particular currency or when the Fund does not own assets denominated in that currency. The Fund may also engage in currency transactions in an attempt to take advantage of certain inefficiencies in the currency exchange market, to increase its exposure to a foreign currency or to shift exposure to foreign currency fluctuations from one currency to another. In managing the Fund's currency exposure from foreign securities, the Sub-Advisers may buy and sell currencies for hedging or for speculative purposes.

The Fund may also invest in futures contracts, forward contracts and swaps for speculative or hedging purposes. Futures contracts, forward contracts and swaps are used to synthetically obtain exposure to the securities identified above or baskets of such securities and to manage the Fund's interest rate duration and yield curve exposure. These derivatives are also used to mitigate the Fund's overall level of risk and/or the Fund's risk to particular types of securities, currencies or market segments. Interest rate swaps are further used to manage the Fund's yield spread sensitivity. When the Fund seeks to take an active long or short position with respect to the likelihood of an event of default of a security or basket of securities, the Fund may use credit default swaps. The Fund may buy credit default swaps in an attempt to manage credit risk where the Fund has credit exposure to an issuer and the Fund may sell credit default swaps to more efficiently gain credit exposure to such security or basket of securities.

The Fund will also invest in securities rated below investment grade (junk bonds). However, in general, the Fund will purchase bonds with a rating of CCC or above. The Fund also invests a portion of its assets in bank loans, which are generally non-investment grade floating rate instruments. The Fund may invest in bank loans in the form of participations in the loans or assignments of all or a portion of the loans from third parties.

The Fund may purchase shares of exchange-traded funds (ETFs) to gain exposure to a particular portion of the market while awaiting an opportunity to purchase securities or other instruments directly. Due to its investment strategy, the Fund may buy and sell securities and other instruments frequently.

Principal Risks

Asset-Backed Securities Risk — Payment of principal and interest on asset-backed securities is dependent largely on the cash flows generated by the assets backing the securities. Securitization trusts generally do not have any assets or sources of funds other than the receivables and related property they own, and asset-backed securities are generally not insured or guaranteed by the related sponsor or any other entity. Asset-backed securities may be more illiquid than more conventional types of fixed-income securities that the Fund acquires.

Bank Loans Risk — With respect to bank loans, the Fund will assume the credit risk of both the borrower and the lender that is selling the participation. The Fund may also have difficulty disposing of bank loans because, in certain cases, the market for such instruments is not highly liquid.

Below Investment Grade Securities (Junk Bonds) Risk — Fixed income securities rated below investment grade (junk bonds) involve greater risks of default or downgrade and are generally more volatile than investment grade securities because the prospect for repayment of principal and interest of many of these securities is speculative. Because these securities typically offer a higher rate of return to compensate investors for these risks, they are sometimes referred to as "high yield bonds," but there is no guarantee that an investment in these securities will result in a high rate of return.

Corporate Fixed Income Securities Risk — Corporate fixed income securities respond to economic developments, especially changes in interest rates, as well as perceptions of the creditworthiness and business prospects of individual issuers.

Credit Risk — The risk that the issuer of a security or the counterparty to a contract will default or otherwise become unable to honor a financial obligation.

Currency Risk — As a result of the Fund's investments in securities or other investments denominated in, and/or receiving revenues in, foreign currencies and the Fund's active management of its currency exposures, the Fund will be subject to currency risk. Currency risk is the risk that foreign currencies will decline in value relative to the U.S. dollar or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency hedged. In either event, the dollar value of an investment in the Fund would be adversely affected. Due to the Fund's active positions in currencies, it will be subject to the risk that currency exchange rates may fluctuate in response to, among other things, changes in interest rates, intervention (or failure to intervene) by U.S. or foreign governments, central banks or supranational entities, or by the imposition of currency controls or other political developments in the United States or abroad.

Derivatives Risk — The Fund's use of swaps, futures and forward contracts is subject to market risk, leverage risk, correlation risk and liquidity risk. Leverage risk, liquidity risk and market risk are described below. Many over-the-counter (OTC) derivative instruments will not have liquidity beyond the counterparty to the instrument. Correlation risk is the risk that changes in the value of the derivative may not correlate perfectly with the underlying asset, rate or index. The Fund's use of swaps and forward contracts is also subject to credit risk and valuation risk. Valuation risk is the risk that the derivative may be difficult to value and/or valued incorrectly. Credit risk is described above. Each of the above risks could cause the Fund to lose more than the principal amount invested in a derivative instrument. Some derivatives have the potential for unlimited loss, regardless of the size of the Fund's initial investment. The other parties to certain derivative contracts present the same types of credit risk as issuers of fixed income securities. The Fund's use of derivatives may also increase the amount of taxes payable by shareholders. Both U.S. and non-U.S. regulators are in the process of adopting and implementing regulations governing derivatives markets, the ultimate impact of which remains unclear.

Duration Risk — The longer-term securities in which the Fund may invest tend to be more volatile than shorter-term securities. A portfolio with a longer average portfolio duration is more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration.

Exchange-Traded Funds (ETFs) Risk — The risks of owning shares of an ETF generally reflect the risks of owning the underlying securities the ETF is designed to track, although lack of liquidity in an ETF could result in its value being more volatile than the underlying portfolio securities. When the Fund invests in an ETF, in addition to directly bearing the expenses associated with its own operations, it will bear a pro rata portion of the ETF's expenses.

Extension Risk — The risk that rising interest rates may extend the duration of a fixed income security, typically reducing the security's value.

Fixed Income Market Risk — The prices of the Fund's fixed income securities respond to economic developments, particularly interest rate changes, as well as to perceptions about the creditworthiness of individual issuers, including governments and their agencies. Generally, the Fund's fixed income securities will decrease in value if interest rates rise and vice versa. In a low interest rate environment, risks associated with rising rates are heightened. Declines in dealer market-making capacity as a result of structural or regulatory changes could further decrease liquidity and/or increase volatility in the fixed income markets. In the case of foreign securities, price fluctuations will reflect international economic and political events, as well as changes in currency valuations relative to the U.S. dollar. In response to these events, the Fund's value may fluctuate and/or the Fund may experience increased redemptions from shareholders, which may impact the Fund's liquidity or force the Fund to sell securities into a declining or illiquid market.

Foreign Investment/Emerging Markets Risk — The risk that non-U.S. securities may be subject to additional risks due to, among other things, political, social and economic developments abroad, currency movements and different legal, regulatory and tax environments. These additional risks may be heightened with respect to emerging market countries because political turmoil and rapid changes in economic conditions are more likely to occur in these countries.

Foreign Sovereign Debt Securities Risk — The risks that: (i) the governmental entity that controls the repayment of sovereign debt may not be willing or able to repay the principal and/or interest when it becomes due because of factors such as debt service burden, political constraints, cash flow problems and other national economic factors; (ii) governments may default on their debt securities, which may require holders of such securities to participate in debt rescheduling or additional lending to defaulting governments; and (iii) there is no bankruptcy proceeding by which defaulted sovereign debt may be collected in whole or in part.

Interest Rate Risk — The risk that a rise in interest rates will cause a fall in the value of fixed income securities, including U.S. Government securities, in which the Fund invests. Although U.S. Government securities are considered to be among the safest investments, they are not guaranteed against price movements due to changing interest rates. A low interest rate environment may present greater interest rate risk, because there may be a greater likelihood of rates increasing and rates may increase more rapidly.

Investment Style Risk — The risk that developed international fixed income securities may underperform other segments of the fixed income markets or the fixed income markets as a whole.

Leverage Risk — The Fund's use of derivatives may result in the Fund's total investment exposure substantially exceeding the value of its portfolio securities and the Fund's investment returns depending substantially on the performance of securities that the Fund may not directly own. The use of leverage can amplify the effects of market volatility on the Fund's share price and may also cause the Fund to liquidate portfolio positions when it would not be advantageous to do so in order to satisfy its obligations. The Fund's use of leverage may result in a heightened risk of investment loss.

Liquidity Risk — The risk that certain securities may be difficult or impossible to sell at the time and the price that the Fund would like. The Fund may have to lower the price of the security, sell other securities instead or forego an investment opportunity, any of which could have a negative effect on Fund management or performance.

Market Risk — The risk that the market value of a security may move up and down, sometimes rapidly and unpredictably. Market risk may affect a single issuer, an industry, a sector or the equity or bond market as a whole.

Mortgage-Backed Securities Risk — Mortgage-backed securities are affected significantly by the rate of prepayments and modifications of the mortgage loans backing those securities, as well as by other factors such as borrower defaults, delinquencies, realized or liquidation losses and other shortfalls. Mortgage-backed securities are particularly sensitive to prepayment risk, which is described below, given that the term to maturity for mortgage loans is generally substantially longer than the expected lives of those securities; however, the timing and amount of prepayments cannot be accurately predicted. The timing of changes in the rate of prepayments of the mortgage loans may significantly affect the Fund's actual yield to maturity on any mortgage-backed securities, even if the average rate of principal payments is consistent with the Fund's expectation. Along with prepayment risk, mortgage-backed securities are significantly affected by interest rate risk, which is described above. In a low interest rate environment, mortgage loan prepayments would generally be expected to increase due to factors such as refinancings and loan modifications at lower interest rates. In contrast, if prevailing interest rates rise, prepayments of mortgage loans would generally be expected to decline and therefore extend the weighted average lives of mortgage-backed securities held or acquired by the Fund.

Non-Diversified Risk — The Fund is non-diversified, which means that it may invest in the securities of relatively few issuers. As a result, the Fund may be more susceptible to a single adverse economic or political occurrence affecting one or more of these issuers and may experience increased volatility due to its investments in those securities.

Portfolio Turnover Risk — Due to its investment strategy, the Fund may buy and sell securities frequently. This may result in higher transaction costs and additional capital gains tax liabilities, which may affect the Fund's performance.

Prepayment Risk — The risk that in a declining interest rate environment, fixed income securities with stated interest rates may have the principal paid earlier than expected, requiring the Fund to invest the proceeds at generally lower interest rates.

U.S. Government Securities Risk — Although U.S. Government securities are considered to be among the safest investments, they are not guaranteed against price movements due to changing interest rates. Obligations issued by some U.S. Government agencies are backed by the U.S. Treasury, while others are backed solely by the ability of the agency to borrow from the U.S. Treasury or by the agency's own resources.

Investing in the Fund involves risk, and there is no guarantee that the Fund will achieve its investment goal. You could lose money on your investment in the Fund, just as you could with other investments. 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.

Performance Information

The bar chart and the performance table below provide some indication of the risks of investing in the Class Y Shares of the Fund by showing changes in the Fund's performance from year to year for the past ten calendar years and by showing how the Fund's average annual returns for 1, 5 and 10 years, and since the Fund's inception, compare with those of a broad measure of market performance. The performance information shown is based on full calendar years. The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future. For current performance information, please call 1-800-DIAL-SEI.

Best Quarter: 6.35% (09/30/09)
Worst Quarter: -3.02% (06/30/15)

Average Annual Total Returns (for the periods ended December 31, 2017)

The Fund's Class Y Shares commenced operations on October 30, 2015. For full calendar years through December 31, 2015, the performance of the Fund's Class F Shares is shown. The Fund's Class F Shares are offered in a separate prospectus. Because Class Y Shares are invested in the same portfolio of securities, returns for Class Y Shares would have been substantially similar to those of Class F Shares, shown here, and would have differed only to the extent that Class Y Shares have lower total annual fund operating expenses than Class F Shares.

After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Your actual after-tax returns will depend on your tax situation and may differ from those shown. After-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts.

Average Annual Returns - Class Y Prospectus - SIT INTERNATIONAL FIXED INCOME FUND	Label	Average Annual Returns, 1 Year		Average Annual Returns, 5 Years		Average Annual Returns, 10 Years		Average Annual Returns, Since Inception		Average Annual Returns, Inception Date
Class Y	Return Before Taxes	2.10%	[1]	2.98%	[1]	3.55%	[1]	4.29%	[1]	Sep. 01, 1993
After Taxes on Distributions | Class Y	Return After Taxes on Distributions	2.10%	[1]	1.49%	[1]	1.96%	[1]	2.72%	[1]
After Taxes on Distributions and Sale of Fund Shares | Class Y	Return After Taxes on Distributions and Sale of Fund Shares	1.19%	[1]	1.60%	[1]	2.07%	[1]	2.74%	[1]
Bloomberg Barclays Global Aggregate ex-US Index, Hedged Return (reflects no deduction for fees, expenses or taxes)	Bloomberg Barclays Global Aggregate ex-US Index, Hedged Return (reflects no deduction for fees, expenses or taxes)	2.48%		3.70%		4.23%		5.65%	[2]	Sep. 30, 1993

[1] The Fund's Class Y Shares commenced operations on October 30, 2015. For periods prior to October 30, 2015, the performance of the Fund's Class F Shares has been used. Returns for Class Y Shares would have been substantially similar to those of Class F Shares and would have differed only to the extent that Class Y Shares have lower total annual fund operating expenses than Class F Shares.

[2] Index returns are shown from September 30, 1993.

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Class Y Prospectus | SIT INTERNATIONAL FIXED INCOME FUND

Risk/Return:

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Risk/Return [Heading]

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SIT INTERNATIONAL FIXED INCOME FUND

Objective [Heading]

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Investment Goal

Objective, Primary [Text Block]

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Capital appreciation and current income.

Expense [Heading]

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Fees and Expenses

Expense Narrative [Text Block]

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The following tables describe the fees and expenses that you may pay if you buy and hold Fund shares.

Operating Expenses Caption [Text]

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ANNUAL FUND OPERATING EXPENSES (expenses that you pay each year as a percentage of the value of your investment)

Portfolio Turnover [Heading]

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PORTFOLIO TURNOVER

Portfolio Turnover [Text Block]

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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 Fund operating expenses or in the Example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 113% of the average value of its portfolio.

Portfolio Turnover, Rate

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113.00%

Expense Example [Heading]

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EXAMPLE

Expense Example Narrative [Text Block]

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This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Fund's operating expenses remain the same.

Expense Example by, Year, Caption [Text]

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Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Strategy [Heading]

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Principal Investment Strategies

Strategy Narrative [Text Block]

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Under normal circumstances, the International Fixed Income Fund will invest at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in fixed income securities. The Fund will invest primarily in investment grade foreign government and corporate fixed income securities, as well as foreign mortgage-backed and/or asset-backed fixed income securities, of issuers located in at least three countries other than the U.S. (including, to a lesser extent, emerging market countries). It is expected that at least 40% of the Fund's assets will be invested in non-U.S. securities. Other fixed income securities in which the Fund may invest include: (i) securities issued or guaranteed by the U.S. Government and its agencies and instrumentalities and obligations of U.S. commercial banks, such as certificates of deposit, time deposits, bankers' acceptances and bank notes; (ii) U.S. corporate debt securities and mortgage-backed and asset-backed securities; and (iii) obligations of supranational entities.

The Fund uses a multi-manager approach, relying upon a number of sub-advisers (each, a Sub-Adviser and collectively, the Sub-Advisers) with differing investment philosophies to manage portions of the Fund's portfolio under the general supervision of SEI Investments Management Corporation (SIMC), the Fund's adviser. In selecting investments for the Fund, the Sub-Advisers choose securities issued by corporations and governments located in various countries, looking for opportunities to achieve capital appreciation and gain, as well as current income. There are no restrictions on the Fund's average portfolio maturity or on the maturity of any specific security.

The Sub-Advisers may seek to enhance the Fund's return by actively managing the Fund's foreign currency exposure. In managing the Fund's currency exposure, the Sub-Advisers buy and sell currencies (i.e., take long or short positions) using derivatives, principally futures, foreign currency forward contracts and currency swaps. The Fund may take long and short positions in foreign currencies in excess of the value of the Fund's assets denominated in a particular currency or when the Fund does not own assets denominated in that currency. The Fund may also engage in currency transactions in an attempt to take advantage of certain inefficiencies in the currency exchange market, to increase its exposure to a foreign currency or to shift exposure to foreign currency fluctuations from one currency to another. In managing the Fund's currency exposure from foreign securities, the Sub-Advisers may buy and sell currencies for hedging or for speculative purposes.

The Fund may also invest in futures contracts, forward contracts and swaps for speculative or hedging purposes. Futures contracts, forward contracts and swaps are used to synthetically obtain exposure to the securities identified above or baskets of such securities and to manage the Fund's interest rate duration and yield curve exposure. These derivatives are also used to mitigate the Fund's overall level of risk and/or the Fund's risk to particular types of securities, currencies or market segments. Interest rate swaps are further used to manage the Fund's yield spread sensitivity. When the Fund seeks to take an active long or short position with respect to the likelihood of an event of default of a security or basket of securities, the Fund may use credit default swaps. The Fund may buy credit default swaps in an attempt to manage credit risk where the Fund has credit exposure to an issuer and the Fund may sell credit default swaps to more efficiently gain credit exposure to such security or basket of securities.

The Fund will also invest in securities rated below investment grade (junk bonds). However, in general, the Fund will purchase bonds with a rating of CCC or above. The Fund also invests a portion of its assets in bank loans, which are generally non-investment grade floating rate instruments. The Fund may invest in bank loans in the form of participations in the loans or assignments of all or a portion of the loans from third parties.

The Fund may purchase shares of exchange-traded funds (ETFs) to gain exposure to a particular portion of the market while awaiting an opportunity to purchase securities or other instruments directly. Due to its investment strategy, the Fund may buy and sell securities and other instruments frequently.

Risk [Heading]

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Principal Risks

Risk Narrative [Text Block]

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Asset-Backed Securities Risk — Payment of principal and interest on asset-backed securities is dependent largely on the cash flows generated by the assets backing the securities. Securitization trusts generally do not have any assets or sources of funds other than the receivables and related property they own, and asset-backed securities are generally not insured or guaranteed by the related sponsor or any other entity. Asset-backed securities may be more illiquid than more conventional types of fixed-income securities that the Fund acquires.

Bank Loans Risk — With respect to bank loans, the Fund will assume the credit risk of both the borrower and the lender that is selling the participation. The Fund may also have difficulty disposing of bank loans because, in certain cases, the market for such instruments is not highly liquid.

Below Investment Grade Securities (Junk Bonds) Risk — Fixed income securities rated below investment grade (junk bonds) involve greater risks of default or downgrade and are generally more volatile than investment grade securities because the prospect for repayment of principal and interest of many of these securities is speculative. Because these securities typically offer a higher rate of return to compensate investors for these risks, they are sometimes referred to as "high yield bonds," but there is no guarantee that an investment in these securities will result in a high rate of return.

Corporate Fixed Income Securities Risk — Corporate fixed income securities respond to economic developments, especially changes in interest rates, as well as perceptions of the creditworthiness and business prospects of individual issuers.

Credit Risk — The risk that the issuer of a security or the counterparty to a contract will default or otherwise become unable to honor a financial obligation.

Currency Risk — As a result of the Fund's investments in securities or other investments denominated in, and/or receiving revenues in, foreign currencies and the Fund's active management of its currency exposures, the Fund will be subject to currency risk. Currency risk is the risk that foreign currencies will decline in value relative to the U.S. dollar or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency hedged. In either event, the dollar value of an investment in the Fund would be adversely affected. Due to the Fund's active positions in currencies, it will be subject to the risk that currency exchange rates may fluctuate in response to, among other things, changes in interest rates, intervention (or failure to intervene) by U.S. or foreign governments, central banks or supranational entities, or by the imposition of currency controls or other political developments in the United States or abroad.

Derivatives Risk — The Fund's use of swaps, futures and forward contracts is subject to market risk, leverage risk, correlation risk and liquidity risk. Leverage risk, liquidity risk and market risk are described below. Many over-the-counter (OTC) derivative instruments will not have liquidity beyond the counterparty to the instrument. Correlation risk is the risk that changes in the value of the derivative may not correlate perfectly with the underlying asset, rate or index. The Fund's use of swaps and forward contracts is also subject to credit risk and valuation risk. Valuation risk is the risk that the derivative may be difficult to value and/or valued incorrectly. Credit risk is described above. Each of the above risks could cause the Fund to lose more than the principal amount invested in a derivative instrument. Some derivatives have the potential for unlimited loss, regardless of the size of the Fund's initial investment. The other parties to certain derivative contracts present the same types of credit risk as issuers of fixed income securities. The Fund's use of derivatives may also increase the amount of taxes payable by shareholders. Both U.S. and non-U.S. regulators are in the process of adopting and implementing regulations governing derivatives markets, the ultimate impact of which remains unclear.

Duration Risk — The longer-term securities in which the Fund may invest tend to be more volatile than shorter-term securities. A portfolio with a longer average portfolio duration is more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration.

Exchange-Traded Funds (ETFs) Risk — The risks of owning shares of an ETF generally reflect the risks of owning the underlying securities the ETF is designed to track, although lack of liquidity in an ETF could result in its value being more volatile than the underlying portfolio securities. When the Fund invests in an ETF, in addition to directly bearing the expenses associated with its own operations, it will bear a pro rata portion of the ETF's expenses.

Extension Risk — The risk that rising interest rates may extend the duration of a fixed income security, typically reducing the security's value.

Fixed Income Market Risk — The prices of the Fund's fixed income securities respond to economic developments, particularly interest rate changes, as well as to perceptions about the creditworthiness of individual issuers, including governments and their agencies. Generally, the Fund's fixed income securities will decrease in value if interest rates rise and vice versa. In a low interest rate environment, risks associated with rising rates are heightened. Declines in dealer market-making capacity as a result of structural or regulatory changes could further decrease liquidity and/or increase volatility in the fixed income markets. In the case of foreign securities, price fluctuations will reflect international economic and political events, as well as changes in currency valuations relative to the U.S. dollar. In response to these events, the Fund's value may fluctuate and/or the Fund may experience increased redemptions from shareholders, which may impact the Fund's liquidity or force the Fund to sell securities into a declining or illiquid market.

Foreign Investment/Emerging Markets Risk — The risk that non-U.S. securities may be subject to additional risks due to, among other things, political, social and economic developments abroad, currency movements and different legal, regulatory and tax environments. These additional risks may be heightened with respect to emerging market countries because political turmoil and rapid changes in economic conditions are more likely to occur in these countries.

Foreign Sovereign Debt Securities Risk — The risks that: (i) the governmental entity that controls the repayment of sovereign debt may not be willing or able to repay the principal and/or interest when it becomes due because of factors such as debt service burden, political constraints, cash flow problems and other national economic factors; (ii) governments may default on their debt securities, which may require holders of such securities to participate in debt rescheduling or additional lending to defaulting governments; and (iii) there is no bankruptcy proceeding by which defaulted sovereign debt may be collected in whole or in part.

Interest Rate Risk — The risk that a rise in interest rates will cause a fall in the value of fixed income securities, including U.S. Government securities, in which the Fund invests. Although U.S. Government securities are considered to be among the safest investments, they are not guaranteed against price movements due to changing interest rates. A low interest rate environment may present greater interest rate risk, because there may be a greater likelihood of rates increasing and rates may increase more rapidly.

Investment Style Risk — The risk that developed international fixed income securities may underperform other segments of the fixed income markets or the fixed income markets as a whole.

Leverage Risk — The Fund's use of derivatives may result in the Fund's total investment exposure substantially exceeding the value of its portfolio securities and the Fund's investment returns depending substantially on the performance of securities that the Fund may not directly own. The use of leverage can amplify the effects of market volatility on the Fund's share price and may also cause the Fund to liquidate portfolio positions when it would not be advantageous to do so in order to satisfy its obligations. The Fund's use of leverage may result in a heightened risk of investment loss.

Liquidity Risk — The risk that certain securities may be difficult or impossible to sell at the time and the price that the Fund would like. The Fund may have to lower the price of the security, sell other securities instead or forego an investment opportunity, any of which could have a negative effect on Fund management or performance.

Market Risk — The risk that the market value of a security may move up and down, sometimes rapidly and unpredictably. Market risk may affect a single issuer, an industry, a sector or the equity or bond market as a whole.

Mortgage-Backed Securities Risk — Mortgage-backed securities are affected significantly by the rate of prepayments and modifications of the mortgage loans backing those securities, as well as by other factors such as borrower defaults, delinquencies, realized or liquidation losses and other shortfalls. Mortgage-backed securities are particularly sensitive to prepayment risk, which is described below, given that the term to maturity for mortgage loans is generally substantially longer than the expected lives of those securities; however, the timing and amount of prepayments cannot be accurately predicted. The timing of changes in the rate of prepayments of the mortgage loans may significantly affect the Fund's actual yield to maturity on any mortgage-backed securities, even if the average rate of principal payments is consistent with the Fund's expectation. Along with prepayment risk, mortgage-backed securities are significantly affected by interest rate risk, which is described above. In a low interest rate environment, mortgage loan prepayments would generally be expected to increase due to factors such as refinancings and loan modifications at lower interest rates. In contrast, if prevailing interest rates rise, prepayments of mortgage loans would generally be expected to decline and therefore extend the weighted average lives of mortgage-backed securities held or acquired by the Fund.

Non-Diversified Risk — The Fund is non-diversified, which means that it may invest in the securities of relatively few issuers. As a result, the Fund may be more susceptible to a single adverse economic or political occurrence affecting one or more of these issuers and may experience increased volatility due to its investments in those securities.

Portfolio Turnover Risk — Due to its investment strategy, the Fund may buy and sell securities frequently. This may result in higher transaction costs and additional capital gains tax liabilities, which may affect the Fund's performance.

Prepayment Risk — The risk that in a declining interest rate environment, fixed income securities with stated interest rates may have the principal paid earlier than expected, requiring the Fund to invest the proceeds at generally lower interest rates.

U.S. Government Securities Risk — Although U.S. Government securities are considered to be among the safest investments, they are not guaranteed against price movements due to changing interest rates. Obligations issued by some U.S. Government agencies are backed by the U.S. Treasury, while others are backed solely by the ability of the agency to borrow from the U.S. Treasury or by the agency's own resources.

Investing in the Fund involves risk, and there is no guarantee that the Fund will achieve its investment goal. You could lose money on your investment in the Fund, just as you could with other investments. 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.

Risk Lose Money [Text]

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Investing in the Fund involves risk, and there is no guarantee that the Fund will achieve its investment goal. You could lose money on your investment in the Fund, just as you could with other investments.

Risk Nondiversified Status [Text]

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The Fund is non-diversified, which means that it may invest in the securities of relatively few issuers. As a result, the Fund may be more susceptible to a single adverse economic or political occurrence affecting one or more of these issuers and may experience increased volatility due to its investments in those securities.

Risk Not Insured Depository Institution [Text]

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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.

Bar Chart and Performance Table [Heading]

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Performance Information

Performance Narrative [Text Block]

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The bar chart and the performance table below provide some indication of the risks of investing in the Class Y Shares of the Fund by showing changes in the Fund's performance from year to year for the past ten calendar years and by showing how the Fund's average annual returns for 1, 5 and 10 years, and since the Fund's inception, compare with those of a broad measure of market performance. The performance information shown is based on full calendar years. The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future. For current performance information, please call 1-800-DIAL-SEI.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

The bar chart and the performance table below provide some indication of the risks of investing in the Class Y Shares of the Fund by showing changes in the Fund's performance from year to year for the past ten calendar years and by showing how the Fund's average annual returns for 1, 5 and 10 years, and since the Fund's inception, compare with those of a broad measure of market performance.

Performance Availability Phone [Text]

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1-800-DIAL-SEI

Performance Past Does Not Indicate Future [Text]

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The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future.

Bar Chart Closing [Text Block]

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Best Quarter: 6.35% (09/30/09)
Worst Quarter: -3.02% (06/30/15)

Bar Chart, Returns for Class Not Offered in Prospectus [Text]

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The Fund's Class F Shares are offered in a separate prospectus.

Highest Quarterly Return, Label

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Best Quarter:

Highest Quarterly Return, Date

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Sep. 30, 2009

Highest Quarterly Return

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6.35%

Lowest Quarterly Return, Label

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Worst Quarter:

Lowest Quarterly Return, Date

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Jun. 30, 2015

Lowest Quarterly Return

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(3.02%)

Performance Table Heading

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Average Annual Total Returns (for the periods ended December 31, 2017)

Index No Deduction for Fees, Expenses, Taxes [Text]

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(reflects no deduction for fees, expenses or taxes)

Performance Table Uses Highest Federal Rate

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After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes.

Performance Table Not Relevant to Tax Deferred

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Your actual after-tax returns will depend on your tax situation and may differ from those shown. After-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts.

Performance Table Narrative

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The Fund's Class Y Shares commenced operations on October 30, 2015. For full calendar years through December 31, 2015, the performance of the Fund's Class F Shares is shown. The Fund's Class F Shares are offered in a separate prospectus. Because Class Y Shares are invested in the same portfolio of securities, returns for Class Y Shares would have been substantially similar to those of Class F Shares, shown here, and would have differed only to the extent that Class Y Shares have lower total annual fund operating expenses than Class F Shares.

After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Your actual after-tax returns will depend on your tax situation and may differ from those shown. After-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts.

Class Y Prospectus | SIT INTERNATIONAL FIXED INCOME FUND | Bloomberg Barclays Global Aggregate ex-US Index, Hedged Return (reflects no deduction for fees, expenses or taxes)

Risk/Return:

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Label

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Bloomberg Barclays Global Aggregate ex-US Index, Hedged Return (reflects no deduction for fees, expenses or taxes)

Average Annual Returns, 1 Year

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2.48%

Average Annual Returns, 5 Years

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3.70%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

4.23%

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

5.65%

^[1]

Average Annual Returns, Inception Date

rr_AverageAnnualReturnInceptionDate

Sep. 30, 1993

Class Y Prospectus | SIT INTERNATIONAL FIXED INCOME FUND | Class Y

Risk/Return:

rr_RiskReturnAbstract

Management Fees

rr_ManagementFeesOverAssets

0.30%

Distribution (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

none

Other Expenses

rr_OtherExpensesOverAssets

0.53%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

0.83%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

$ 85

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

265

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

460

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

$ 1,025

Annual Return 2008

rr_AnnualReturn2008

(5.22%)

Annual Return 2009

rr_AnnualReturn2009

11.01%

Annual Return 2010

rr_AnnualReturn2010

5.33%

Annual Return 2011

rr_AnnualReturn2011

3.51%

Annual Return 2012

rr_AnnualReturn2012

6.68%

Annual Return 2013

rr_AnnualReturn2013

(0.11%)

Annual Return 2014

rr_AnnualReturn2014

7.92%

Annual Return 2015

rr_AnnualReturn2015

0.39%

Annual Return 2016

rr_AnnualReturn2016

4.75%

Annual Return 2017

rr_AnnualReturn2017

2.10%

Label

rr_AverageAnnualReturnLabel

Return Before Taxes

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

2.10%

^[2]

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

2.98%

^[2]

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

3.55%

^[2]

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

4.29%

^[2]

Average Annual Returns, Inception Date

rr_AverageAnnualReturnInceptionDate

Sep. 01, 1993

Class Y Prospectus | SIT INTERNATIONAL FIXED INCOME FUND | Class Y | After Taxes on Distributions

Risk/Return:

rr_RiskReturnAbstract

Label

rr_AverageAnnualReturnLabel

Return After Taxes on Distributions

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

2.10%

^[2]

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

1.49%

^[2]

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

1.96%

^[2]

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

2.72%

^[2]

Class Y Prospectus | SIT INTERNATIONAL FIXED INCOME FUND | Class Y | After Taxes on Distributions and Sale of Fund Shares

Risk/Return:

rr_RiskReturnAbstract

Label

rr_AverageAnnualReturnLabel

Return After Taxes on Distributions and Sale of Fund Shares

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

1.19%

^[2]

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

1.60%

^[2]

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

2.07%

^[2]

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

2.74%

^[2]

[1] Index returns are shown from September 30, 1993.

[2] The Fund's Class Y Shares commenced operations on October 30, 2015. For periods prior to October 30, 2015, the performance of the Fund's Class F Shares has been used. Returns for Class Y Shares would have been substantially similar to those of Class F Shares and would have differed only to the extent that Class Y Shares have lower total annual fund operating expenses than Class F Shares.

XML

Class Y Prospectus | SIT EMERGING MARKETS DEBT FUND

SIT EMERGING MARKETS DEBT FUND

Investment Goal

Maximize total return.

Fees and Expenses

The following tables describe the fees and expenses that you may pay if you buy and hold Fund shares.

ANNUAL FUND OPERATING EXPENSES (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses	Class Y Prospectus SIT EMERGING MARKETS DEBT FUND Class Y
Management Fees	0.85%
Distribution (12b-1) Fees	none
Other Expenses	0.53%
Total Annual Fund Operating Expenses	1.38%

EXAMPLE

This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Fund's operating expenses remain the same.

Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Expense Example	1 Year	3 Years	5 Years	10 Years
Class Y Prospectus | SIT EMERGING MARKETS DEBT FUND | Class Y | USD ($)	140	437	755	1,657

PORTFOLIO TURNOVER

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 Fund 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.

Principal Investment Strategies

Under normal circumstances, the Emerging Markets Debt Fund will invest at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in fixed income securities of emerging market issuers. The Fund will invest in debt securities of government, government-related and corporate issuers in emerging market countries, as well as entities organized to restructure the outstanding debt of such issuers. The Fund may obtain its exposures by investing directly (e.g., in fixed income securities and other instruments) or indirectly/synthetically (e.g., through the use of derivative instruments, principally futures contracts, forward contracts and swaps and structured securities, such as credit-linked and inflation-linked notes). The Fund may invest in swaps based on a single security or an index of securities, including interest rate swaps, credit default swaps, currency swaps and fully-funded total return swaps. Emerging market countries are those countries that are: (i) characterized as developing or emerging by any of the World Bank, the United Nations, the International Finance Corporation, or the European Bank for Reconstruction and Development; (ii) included in an emerging markets index by a recognized index provider; or (iii) countries with similar developing or emerging characteristics as countries classified as emerging market countries pursuant to sub-paragraph (i) and (ii) above, in each case determined at the time of purchase.

The Fund uses a multi-manager approach, relying upon a number of sub-advisers (each, a Sub-Adviser and collectively, the Sub-Advisers) with differing investment philosophies to manage portions of the Fund's portfolio under the general supervision of SEI Investments Management Corporation (SIMC), the Fund's adviser. The Sub-Advisers will spread the Fund's holdings across a number of countries and industries to limit its exposure to any single emerging market economy and may not invest more than 25% of its assets in any single country. There are no restrictions on the Fund's average portfolio maturity or on the maturity of any specific security. There is no minimum rating standard for the Fund's securities, and the Fund's securities will generally be in the lower or lowest rating categories (including those below the fourth highest rating category by a Nationally Recognized Statistical Rating Organization (NRSRO), commonly referred to as junk bonds).

The Sub-Advisers may seek to enhance the Fund's return by actively managing the Fund's foreign currency exposure. In managing the Fund's currency exposure, the Sub-Advisers buy and sell currencies (i.e., take long or short positions) using derivatives, principally futures, foreign currency forward contracts, options on foreign currencies and currency swaps. The Fund may take long and short positions in foreign currencies in excess of the value of the Fund's assets denominated in a particular currency or when the Fund does not own assets denominated in that currency. The Fund may also engage in currency transactions in an attempt to take advantage of certain inefficiencies in the currency exchange market, to increase its exposure to a foreign currency or to shift exposure to foreign currency fluctuations from one currency to another. In managing the Fund's currency exposure from foreign securities, the Sub-Advisers may buy and sell currencies for hedging or for speculative purposes.

The Fund may also invest in futures contracts, forward contracts and swaps for speculative or hedging purposes. Futures contracts, forward contracts and swaps are used to synthetically obtain exposure to the securities identified above or baskets of such securities and to manage the Fund's interest rate duration and yield curve exposure. These derivatives are also used to mitigate the Fund's overall level of risk and/or the Fund's risk to particular types of securities, currencies or market segments. Interest rate swaps are further used to manage the Fund's yield spread sensitivity. When the Fund seeks to take an active long or short position with respect to the likelihood of an event of default of a security or basket of securities, the Fund may use credit default swaps. The Fund may buy credit default swaps in an attempt to manage credit risk where the Fund has credit exposure to an issuer and the Fund may sell credit default swaps to more efficiently gain credit exposure to such security or basket of securities.

The Fund may purchase shares of exchange-traded funds (ETFs) to gain exposure to a particular portion of the market while awaiting an opportunity to purchase securities or other instruments directly.

Principal Risks

Below Investment Grade Securities (Junk Bonds) Risk — Fixed income securities rated below investment grade (junk bonds) involve greater risks of default or downgrade and are generally more volatile than investment grade securities because the prospect for repayment of principal and interest of many of these securities is speculative. Because these securities typically offer a higher rate of return to compensate investors for these risks, they are sometimes referred to as "high yield bonds," but there is no guarantee that an investment in these securities will result in a high rate of return.

Corporate Fixed Income Securities Risk — Corporate fixed income securities respond to economic developments, especially changes in interest rates, as well as perceptions of the creditworthiness and business prospects of individual issuers.

Credit Risk — The risk that the issuer of a security or the counterparty to a contract will default or otherwise become unable to honor a financial obligation.

Currency Risk — As a result of the Fund's investments in securities or other investments denominated in, and/or receiving revenues in, foreign currencies and the Fund's active management of its currency exposures, the Fund will be subject to currency risk. Currency risk is the risk that foreign currencies will decline in value relative to the U.S. dollar or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency hedged. In either event, the dollar value of an investment in the Fund would be adversely affected. Due to the Fund's active positions in currencies, it will be subject to the risk that currency exchange rates may fluctuate in response to, among other things, changes in interest rates, intervention (or failure to intervene) by U.S. or foreign governments, central banks or supranational entities, or by the imposition of currency controls or other political developments in the United States or abroad.

Derivatives Risk — The Fund's use of futures contracts, forward contracts, options, swaps and credit-linked notes is subject to market risk, leverage risk, correlation risk and liquidity risk. Leverage risk, liquidity risk and market risk are described below. Many over-the-counter (OTC) derivative instruments will not have liquidity beyond the counterparty to the instrument. Correlation risk is the risk that changes in the value of the derivative may not correlate perfectly with the underlying asset, rate or index. The Fund's use of forward contracts, options, credit-linked notes and swap agreements is also subject to credit risk and valuation risk. Valuation risk is the risk that the derivative may be difficult to value and/or valued incorrectly. Credit risk is described above. Each of the above risks could cause the Fund to lose more than the principal amount invested in a derivative instrument. Some derivatives have the potential for unlimited loss, regardless of the size of the Fund's initial investment. The other parties to certain derivative contracts present the same types of credit risk as issuers of fixed income securities. The Fund's use of derivatives may also increase the amount of taxes payable by shareholders. Both U.S. and non-U.S. regulators are in the process of adopting and implementing regulations governing derivatives markets, the ultimate impact of which remains unclear.

Duration Risk — The longer-term securities in which the Fund may invest tend to be more volatile than shorter-term securities. A portfolio with a longer average portfolio duration is more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration.

Exchange-Traded Funds (ETFs) Risk — The risks of owning shares of an ETF generally reflect the risks of owning the underlying securities the ETF is designed to track, although lack of liquidity in an ETF could result in its value being more volatile than the underlying portfolio securities. When the Fund invests in an ETF, in addition to directly bearing the expenses associated with its own operations, it will bear a pro rata portion of the ETF's expenses.

Extension Risk — The risk that rising interest rates may extend the duration of a fixed income security, typically reducing the security's value.

Fixed Income Market Risk — The prices of the Fund's fixed income securities respond to economic developments, particularly interest rate changes, as well as to perceptions about the creditworthiness of individual issuers, including governments and their agencies. Generally, the Fund's fixed income securities will decrease in value if interest rates rise and vice versa. In a low interest rate environment, risks associated with rising rates are heightened. Declines in dealer market-making capacity as a result of structural or regulatory changes could further decrease liquidity and/or increase volatility in the fixed income markets. In the case of foreign securities, price fluctuations will reflect international economic and political events, as well as changes in currency valuations relative to the U.S. dollar. In response to these events, the Fund's value may fluctuate and/or the Fund may experience increased redemptions from shareholders, which may impact the Fund's liquidity or force the Fund to sell securities into a declining or illiquid market.

Foreign Investment/Emerging Markets Risk — The risk that non-U.S. securities may be subject to additional risks due to, among other things, political, social and economic developments abroad, currency movements and different legal, regulatory and tax environments. These additional risks may be heightened with respect to emerging market countries because political turmoil and rapid changes in economic conditions are more likely to occur in these countries.

Foreign Sovereign Debt Securities Risk — The risks that (i) the governmental entity that controls the repayment of sovereign debt may not be willing or able to repay the principal and/or interest when it becomes due because of factors such as debt service burden, political constraints, cash flow problems and other national economic factors; (ii) governments may default on their debt securities, which may require holders of such securities to participate in debt rescheduling or additional lending to defaulting governments; and (iii) there is no bankruptcy proceeding by which defaulted sovereign debt may be collected in whole or in part.

Interest Rate Risk — The risk that a rise in interest rates will cause a fall in the value of fixed income securities in which the Fund invests. A low interest rate environment may present greater interest rate risk, because there may be a greater likelihood of rates increasing and rates may increase more rapidly.

Investment Style Risk — The risk that emerging market debt securities may underperform other segments of the fixed income markets or the fixed income markets as a whole.

Leverage Risk — The Fund's use of derivatives may result in the Fund's total investment exposure substantially exceeding the value of its portfolio securities and the Fund's investment returns depending substantially on the performance of securities that the Fund may not directly own. The use of leverage can amplify the effects of market volatility on the Fund's share price and may also cause the Fund to liquidate portfolio positions when it would not be advantageous to do so in order to satisfy its obligations. The Fund's use of leverage may result in a heightened risk of investment loss.

Liquidity Risk — The risk that certain securities may be difficult or impossible to sell at the time and the price that the Fund would like. The Fund may have to lower the price of the security, sell other securities instead or forego an investment opportunity, any of which could have a negative effect on Fund management or performance.

Market Risk — The risk that the market value of a security may move up and down, sometimes rapidly and unpredictably. Market risk may affect a single issuer, an industry, a sector or the equity or bond market as a whole.

Non-Diversified Risk — The Fund is non-diversified, which means that it may invest in the securities of relatively few issuers. As a result, the Fund may be more susceptible to a single adverse economic or political occurrence affecting one or more of these issuers and may experience increased volatility due to its investments in those securities.

Prepayment Risk — The risk that in a declining interest rate environment, fixed income securities with stated interest rates may have the principal paid earlier than expected, requiring the Fund to invest the proceeds at generally lower interest rates.

Investing in the Fund involves risk, and there is no guarantee that the Fund will achieve its investment goal. You could lose money on your investment in the Fund, just as you could with other investments. 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.

Performance Information

The bar chart and the performance table below provide some indication of the risks of investing in the Class Y Shares of the Fund by showing changes in the Fund's performance from year to year for the past ten calendar years and by showing how the Fund's average annual returns for 1, 5 and 10 years, and since the Fund's inception, compare with those of a broad measure of market performance. The performance information shown is based on full calendar years. The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future. For current performance information, please call 1-800-DIAL-SEI.

Best Quarter: 15.11% (06/30/09)
Worst Quarter: -13.19% (12/31/08)

Average Annual Total Returns (for the periods ended December 31, 2017)

The Fund's Class Y Shares commenced operations on December 31, 2014. For full calendar years through December 31, 2014, the performance of the Fund's Class F Shares is shown. The Fund's Class F Shares are offered in a separate prospectus. Because Class Y Shares are invested in the same portfolio of securities, returns for Class Y Shares would have been substantially similar to those of Class F Shares, shown here, and would have differed only to the extent that Class Y Shares have lower total annual fund operating expenses than Class F Shares.

This table compares the Fund's average annual total returns to those of a broad-based index and the Fund's 50/50 Blended Benchmark, which consists of the J.P. Morgan Emerging Markets Bond Index (EMBI) Global Diversified Index (50%) and the J.P. Morgan Government Bond Index-Emerging Markets (GBI-EM) Global Diversified Index (50%). The Fund's Blended Benchmark is designed to provide a useful comparison to the Fund's overall performance and more accurately reflect the Fund's investment strategy than the broad-based index.

After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Your actual after-tax returns will depend on your tax situation and may differ from those shown. After-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts.

Average Annual Returns - Class Y Prospectus - SIT EMERGING MARKETS DEBT FUND	Label	Average Annual Returns, 1 Year		Average Annual Returns, 5 Years		Average Annual Returns, 10 Years		Average Annual Returns, Since Inception		Average Annual Returns, Inception Date
Class Y	Return Before Taxes	14.54%	[1]	0.45%	[1]	4.98%	[1]	8.22%	[1]	Jun. 26, 1997
After Taxes on Distributions | Class Y	Return After Taxes on Distributions	12.32%	[1]	(0.73%)	[1]	3.11%	[1]	5.42%	[1]
After Taxes on Distributions and Sale of Fund Shares | Class Y	Return After Taxes on Distributions and Sale of Fund Shares	8.21%	[1]	(0.20%)	[1]	3.15%	[1]	5.40%	[1]
J.P. Morgan EMBI Global Diversified Index Return (reflects no deduction for fees, expenses or taxes)	J.P. Morgan EMBI Global Diversified Index Return (reflects no deduction for fees, expenses or taxes)	10.26%		4.58%		7.29%		8.71%	[2]	Jun. 30, 1997
The Fund's Blended Benchmark Return (reflects no deduction for fees, expenses or taxes)	The Fund's Blended Benchmark Return (reflects no deduction for fees, expenses or taxes)	12.74%		1.53%		5.49%			[3]	Jun. 30, 1997

[1] The Fund's Class Y Shares commenced operations on December 31, 2014. For periods prior to December 31, 2014, the performance of the Fund's Class F Shares has been used. Returns for Class Y Shares would have been substantially similar to those of Class F Shares and would have differed only to the extent that Class Y Shares have lower total annual fund operating expenses than Class F Shares.

[2] Index returns are shown from June 30, 1997.

[3] The Blended Benchmark Return for the "Since Inception" period is not provided because returns for the J.P. Morgan GBI-EM Global Diversified Index Return are not available prior to 2003.

XML

Label

Element

Value

Class Y Prospectus | SIT EMERGING MARKETS DEBT FUND

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

SIT EMERGING MARKETS DEBT FUND

Objective [Heading]

rr_ObjectiveHeading

Investment Goal

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

Maximize total return.

Expense [Heading]

rr_ExpenseHeading

Fees and Expenses

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

The following tables describe the fees and expenses that you may pay if you buy and hold Fund shares.

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

ANNUAL FUND OPERATING EXPENSES (expenses that you pay each year as a percentage of the value of your investment)

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

PORTFOLIO TURNOVER

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 Fund 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 [Heading]

rr_ExpenseExampleHeading

EXAMPLE

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Fund's operating expenses remain the same.

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Strategy [Heading]

rr_StrategyHeading

Principal Investment Strategies

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

Under normal circumstances, the Emerging Markets Debt Fund will invest at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in fixed income securities of emerging market issuers. The Fund will invest in debt securities of government, government-related and corporate issuers in emerging market countries, as well as entities organized to restructure the outstanding debt of such issuers. The Fund may obtain its exposures by investing directly (e.g., in fixed income securities and other instruments) or indirectly/synthetically (e.g., through the use of derivative instruments, principally futures contracts, forward contracts and swaps and structured securities, such as credit-linked and inflation-linked notes). The Fund may invest in swaps based on a single security or an index of securities, including interest rate swaps, credit default swaps, currency swaps and fully-funded total return swaps. Emerging market countries are those countries that are: (i) characterized as developing or emerging by any of the World Bank, the United Nations, the International Finance Corporation, or the European Bank for Reconstruction and Development; (ii) included in an emerging markets index by a recognized index provider; or (iii) countries with similar developing or emerging characteristics as countries classified as emerging market countries pursuant to sub-paragraph (i) and (ii) above, in each case determined at the time of purchase.

The Fund uses a multi-manager approach, relying upon a number of sub-advisers (each, a Sub-Adviser and collectively, the Sub-Advisers) with differing investment philosophies to manage portions of the Fund's portfolio under the general supervision of SEI Investments Management Corporation (SIMC), the Fund's adviser. The Sub-Advisers will spread the Fund's holdings across a number of countries and industries to limit its exposure to any single emerging market economy and may not invest more than 25% of its assets in any single country. There are no restrictions on the Fund's average portfolio maturity or on the maturity of any specific security. There is no minimum rating standard for the Fund's securities, and the Fund's securities will generally be in the lower or lowest rating categories (including those below the fourth highest rating category by a Nationally Recognized Statistical Rating Organization (NRSRO), commonly referred to as junk bonds).

The Sub-Advisers may seek to enhance the Fund's return by actively managing the Fund's foreign currency exposure. In managing the Fund's currency exposure, the Sub-Advisers buy and sell currencies (i.e., take long or short positions) using derivatives, principally futures, foreign currency forward contracts, options on foreign currencies and currency swaps. The Fund may take long and short positions in foreign currencies in excess of the value of the Fund's assets denominated in a particular currency or when the Fund does not own assets denominated in that currency. The Fund may also engage in currency transactions in an attempt to take advantage of certain inefficiencies in the currency exchange market, to increase its exposure to a foreign currency or to shift exposure to foreign currency fluctuations from one currency to another. In managing the Fund's currency exposure from foreign securities, the Sub-Advisers may buy and sell currencies for hedging or for speculative purposes.

The Fund may also invest in futures contracts, forward contracts and swaps for speculative or hedging purposes. Futures contracts, forward contracts and swaps are used to synthetically obtain exposure to the securities identified above or baskets of such securities and to manage the Fund's interest rate duration and yield curve exposure. These derivatives are also used to mitigate the Fund's overall level of risk and/or the Fund's risk to particular types of securities, currencies or market segments. Interest rate swaps are further used to manage the Fund's yield spread sensitivity. When the Fund seeks to take an active long or short position with respect to the likelihood of an event of default of a security or basket of securities, the Fund may use credit default swaps. The Fund may buy credit default swaps in an attempt to manage credit risk where the Fund has credit exposure to an issuer and the Fund may sell credit default swaps to more efficiently gain credit exposure to such security or basket of securities.

The Fund may purchase shares of exchange-traded funds (ETFs) to gain exposure to a particular portion of the market while awaiting an opportunity to purchase securities or other instruments directly.

Risk [Heading]

rr_RiskHeading

Principal Risks

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

Below Investment Grade Securities (Junk Bonds) Risk — Fixed income securities rated below investment grade (junk bonds) involve greater risks of default or downgrade and are generally more volatile than investment grade securities because the prospect for repayment of principal and interest of many of these securities is speculative. Because these securities typically offer a higher rate of return to compensate investors for these risks, they are sometimes referred to as "high yield bonds," but there is no guarantee that an investment in these securities will result in a high rate of return.

Corporate Fixed Income Securities Risk — Corporate fixed income securities respond to economic developments, especially changes in interest rates, as well as perceptions of the creditworthiness and business prospects of individual issuers.

Credit Risk — The risk that the issuer of a security or the counterparty to a contract will default or otherwise become unable to honor a financial obligation.

Currency Risk — As a result of the Fund's investments in securities or other investments denominated in, and/or receiving revenues in, foreign currencies and the Fund's active management of its currency exposures, the Fund will be subject to currency risk. Currency risk is the risk that foreign currencies will decline in value relative to the U.S. dollar or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency hedged. In either event, the dollar value of an investment in the Fund would be adversely affected. Due to the Fund's active positions in currencies, it will be subject to the risk that currency exchange rates may fluctuate in response to, among other things, changes in interest rates, intervention (or failure to intervene) by U.S. or foreign governments, central banks or supranational entities, or by the imposition of currency controls or other political developments in the United States or abroad.

Derivatives Risk — The Fund's use of futures contracts, forward contracts, options, swaps and credit-linked notes is subject to market risk, leverage risk, correlation risk and liquidity risk. Leverage risk, liquidity risk and market risk are described below. Many over-the-counter (OTC) derivative instruments will not have liquidity beyond the counterparty to the instrument. Correlation risk is the risk that changes in the value of the derivative may not correlate perfectly with the underlying asset, rate or index. The Fund's use of forward contracts, options, credit-linked notes and swap agreements is also subject to credit risk and valuation risk. Valuation risk is the risk that the derivative may be difficult to value and/or valued incorrectly. Credit risk is described above. Each of the above risks could cause the Fund to lose more than the principal amount invested in a derivative instrument. Some derivatives have the potential for unlimited loss, regardless of the size of the Fund's initial investment. The other parties to certain derivative contracts present the same types of credit risk as issuers of fixed income securities. The Fund's use of derivatives may also increase the amount of taxes payable by shareholders. Both U.S. and non-U.S. regulators are in the process of adopting and implementing regulations governing derivatives markets, the ultimate impact of which remains unclear.

Duration Risk — The longer-term securities in which the Fund may invest tend to be more volatile than shorter-term securities. A portfolio with a longer average portfolio duration is more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration.

Exchange-Traded Funds (ETFs) Risk — The risks of owning shares of an ETF generally reflect the risks of owning the underlying securities the ETF is designed to track, although lack of liquidity in an ETF could result in its value being more volatile than the underlying portfolio securities. When the Fund invests in an ETF, in addition to directly bearing the expenses associated with its own operations, it will bear a pro rata portion of the ETF's expenses.

Extension Risk — The risk that rising interest rates may extend the duration of a fixed income security, typically reducing the security's value.

Fixed Income Market Risk — The prices of the Fund's fixed income securities respond to economic developments, particularly interest rate changes, as well as to perceptions about the creditworthiness of individual issuers, including governments and their agencies. Generally, the Fund's fixed income securities will decrease in value if interest rates rise and vice versa. In a low interest rate environment, risks associated with rising rates are heightened. Declines in dealer market-making capacity as a result of structural or regulatory changes could further decrease liquidity and/or increase volatility in the fixed income markets. In the case of foreign securities, price fluctuations will reflect international economic and political events, as well as changes in currency valuations relative to the U.S. dollar. In response to these events, the Fund's value may fluctuate and/or the Fund may experience increased redemptions from shareholders, which may impact the Fund's liquidity or force the Fund to sell securities into a declining or illiquid market.

Foreign Investment/Emerging Markets Risk — The risk that non-U.S. securities may be subject to additional risks due to, among other things, political, social and economic developments abroad, currency movements and different legal, regulatory and tax environments. These additional risks may be heightened with respect to emerging market countries because political turmoil and rapid changes in economic conditions are more likely to occur in these countries.

Foreign Sovereign Debt Securities Risk — The risks that (i) the governmental entity that controls the repayment of sovereign debt may not be willing or able to repay the principal and/or interest when it becomes due because of factors such as debt service burden, political constraints, cash flow problems and other national economic factors; (ii) governments may default on their debt securities, which may require holders of such securities to participate in debt rescheduling or additional lending to defaulting governments; and (iii) there is no bankruptcy proceeding by which defaulted sovereign debt may be collected in whole or in part.

Interest Rate Risk — The risk that a rise in interest rates will cause a fall in the value of fixed income securities in which the Fund invests. A low interest rate environment may present greater interest rate risk, because there may be a greater likelihood of rates increasing and rates may increase more rapidly.

Investment Style Risk — The risk that emerging market debt securities may underperform other segments of the fixed income markets or the fixed income markets as a whole.

Leverage Risk — The Fund's use of derivatives may result in the Fund's total investment exposure substantially exceeding the value of its portfolio securities and the Fund's investment returns depending substantially on the performance of securities that the Fund may not directly own. The use of leverage can amplify the effects of market volatility on the Fund's share price and may also cause the Fund to liquidate portfolio positions when it would not be advantageous to do so in order to satisfy its obligations. The Fund's use of leverage may result in a heightened risk of investment loss.

Liquidity Risk — The risk that certain securities may be difficult or impossible to sell at the time and the price that the Fund would like. The Fund may have to lower the price of the security, sell other securities instead or forego an investment opportunity, any of which could have a negative effect on Fund management or performance.

Market Risk — The risk that the market value of a security may move up and down, sometimes rapidly and unpredictably. Market risk may affect a single issuer, an industry, a sector or the equity or bond market as a whole.

Non-Diversified Risk — The Fund is non-diversified, which means that it may invest in the securities of relatively few issuers. As a result, the Fund may be more susceptible to a single adverse economic or political occurrence affecting one or more of these issuers and may experience increased volatility due to its investments in those securities.

Prepayment Risk — The risk that in a declining interest rate environment, fixed income securities with stated interest rates may have the principal paid earlier than expected, requiring the Fund to invest the proceeds at generally lower interest rates.

Investing in the Fund involves risk, and there is no guarantee that the Fund will achieve its investment goal. You could lose money on your investment in the Fund, just as you could with other investments. 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.

Risk Lose Money [Text]

rr_RiskLoseMoney

Investing in the Fund involves risk, and there is no guarantee that the Fund will achieve its investment goal. You could lose money on your investment in the Fund, just as you could with other investments.

Risk Nondiversified Status [Text]

rr_RiskNondiversifiedStatus

The Fund is non-diversified, which means that it may invest in the securities of relatively few issuers. As a result, the Fund may be more susceptible to a single adverse economic or political occurrence affecting one or more of these issuers and may experience increased volatility due to its investments in those securities.

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

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.

Bar Chart and Performance Table [Heading]

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Performance Information

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The bar chart and the performance table below provide some indication of the risks of investing in the Class Y Shares of the Fund by showing changes in the Fund's performance from year to year for the past ten calendar years and by showing how the Fund's average annual returns for 1, 5 and 10 years, and since the Fund's inception, compare with those of a broad measure of market performance. The performance information shown is based on full calendar years. The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future. For current performance information, please call 1-800-DIAL-SEI.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

The bar chart and the performance table below provide some indication of the risks of investing in the Class Y Shares of the Fund by showing changes in the Fund's performance from year to year for the past ten calendar years and by showing how the Fund's average annual returns for 1, 5 and 10 years, and since the Fund's inception, compare with those of a broad measure of market performance.

Performance Additional Market Index [Text]

rr_PerformanceAdditionalMarketIndex

This table compares the Fund's average annual total returns to those of a broad-based index and the Fund's 50/50 Blended Benchmark, which consists of the J.P. Morgan Emerging Markets Bond Index (EMBI) Global Diversified Index (50%) and the J.P. Morgan Government Bond Index-Emerging Markets (GBI-EM) Global Diversified Index (50%). The Fund's Blended Benchmark is designed to provide a useful comparison to the Fund's overall performance and more accurately reflect the Fund's investment strategy than the broad-based index.

Performance Availability Phone [Text]

rr_PerformanceAvailabilityPhone

1-800-DIAL-SEI

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future.

Bar Chart Closing [Text Block]

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Best Quarter: 15.11% (06/30/09)
Worst Quarter: -13.19% (12/31/08)

Bar Chart, Returns for Class Not Offered in Prospectus [Text]

rr_BarChartReturnsForClassNotOfferedInProspectus

The Fund's Class F Shares are offered in a separate prospectus.

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Best Quarter:

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Jun. 30, 2009

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

15.11%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Worst Quarter:

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Dec. 31, 2008

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(13.19%)

Performance Table Heading

rr_PerformanceTableHeading

Average Annual Total Returns (for the periods ended December 31, 2017)

Index No Deduction for Fees, Expenses, Taxes [Text]

rr_IndexNoDeductionForFeesExpensesTaxes

(reflects no deduction for fees, expenses or taxes)

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes.

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

Your actual after-tax returns will depend on your tax situation and may differ from those shown. After-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts.

Performance Table Narrative

rr_PerformanceTableNarrativeTextBlock

The Fund's Class Y Shares commenced operations on December 31, 2014. For full calendar years through December 31, 2014, the performance of the Fund's Class F Shares is shown. The Fund's Class F Shares are offered in a separate prospectus. Because Class Y Shares are invested in the same portfolio of securities, returns for Class Y Shares would have been substantially similar to those of Class F Shares, shown here, and would have differed only to the extent that Class Y Shares have lower total annual fund operating expenses than Class F Shares.

This table compares the Fund's average annual total returns to those of a broad-based index and the Fund's 50/50 Blended Benchmark, which consists of the J.P. Morgan Emerging Markets Bond Index (EMBI) Global Diversified Index (50%) and the J.P. Morgan Government Bond Index-Emerging Markets (GBI-EM) Global Diversified Index (50%). The Fund's Blended Benchmark is designed to provide a useful comparison to the Fund's overall performance and more accurately reflect the Fund's investment strategy than the broad-based index.

After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Your actual after-tax returns will depend on your tax situation and may differ from those shown. After-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts.

Class Y Prospectus | SIT EMERGING MARKETS DEBT FUND | J.P. Morgan EMBI Global Diversified Index Return (reflects no deduction for fees, expenses or taxes)

Risk/Return:

rr_RiskReturnAbstract

Label

rr_AverageAnnualReturnLabel

J.P. Morgan EMBI Global Diversified Index Return (reflects no deduction for fees, expenses or taxes)

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

10.26%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

4.58%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

7.29%

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

8.71%

^[1]

Average Annual Returns, Inception Date

rr_AverageAnnualReturnInceptionDate

Jun. 30, 1997

Class Y Prospectus | SIT EMERGING MARKETS DEBT FUND | The Fund's Blended Benchmark Return (reflects no deduction for fees, expenses or taxes)

Risk/Return:

rr_RiskReturnAbstract

Label

rr_AverageAnnualReturnLabel

The Fund's Blended Benchmark Return (reflects no deduction for fees, expenses or taxes)

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

12.74%

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

1.53%

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

5.49%

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

^[2]

Average Annual Returns, Inception Date

rr_AverageAnnualReturnInceptionDate

Jun. 30, 1997

Class Y Prospectus | SIT EMERGING MARKETS DEBT FUND | Class Y

Risk/Return:

rr_RiskReturnAbstract

Management Fees

rr_ManagementFeesOverAssets

0.85%

Distribution (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

none

Other Expenses

rr_OtherExpensesOverAssets

0.53%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

1.38%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

$ 140

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

437

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

755

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

$ 1,657

Annual Return 2008

rr_AnnualReturn2008

(19.72%)

Annual Return 2009

rr_AnnualReturn2009

40.53%

Annual Return 2010

rr_AnnualReturn2010

14.47%

Annual Return 2011

rr_AnnualReturn2011

4.74%

Annual Return 2012

rr_AnnualReturn2012

17.54%

Annual Return 2013

rr_AnnualReturn2013

(9.59%)

Annual Return 2014

rr_AnnualReturn2014

(1.20%)

Annual Return 2015

rr_AnnualReturn2015

(8.96%)

Annual Return 2016

rr_AnnualReturn2016

9.79%

Annual Return 2017

rr_AnnualReturn2017

14.54%

Label

rr_AverageAnnualReturnLabel

Return Before Taxes

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

14.54%

^[3]

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

0.45%

^[3]

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

4.98%

^[3]

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

8.22%

^[3]

Average Annual Returns, Inception Date

rr_AverageAnnualReturnInceptionDate

Jun. 26, 1997

Class Y Prospectus | SIT EMERGING MARKETS DEBT FUND | Class Y | After Taxes on Distributions

Risk/Return:

rr_RiskReturnAbstract

Label

rr_AverageAnnualReturnLabel

Return After Taxes on Distributions

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

12.32%

^[3]

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

(0.73%)

^[3]

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

3.11%

^[3]

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

5.42%

^[3]

Class Y Prospectus | SIT EMERGING MARKETS DEBT FUND | Class Y | After Taxes on Distributions and Sale of Fund Shares

Risk/Return:

rr_RiskReturnAbstract

Label

rr_AverageAnnualReturnLabel

Return After Taxes on Distributions and Sale of Fund Shares

Average Annual Returns, 1 Year

rr_AverageAnnualReturnYear01

8.21%

^[3]

Average Annual Returns, 5 Years

rr_AverageAnnualReturnYear05

(0.20%)

^[3]

Average Annual Returns, 10 Years

rr_AverageAnnualReturnYear10

3.15%

^[3]

Average Annual Returns, Since Inception

rr_AverageAnnualReturnSinceInception

5.40%

^[3]

[1] Index returns are shown from June 30, 1997.

[2] The Blended Benchmark Return for the "Since Inception" period is not provided because returns for the J.P. Morgan GBI-EM Global Diversified Index Return are not available prior to 2003.

[3] The Fund's Class Y Shares commenced operations on December 31, 2014. For periods prior to December 31, 2014, the performance of the Fund's Class F Shares has been used. Returns for Class Y Shares would have been substantially similar to those of Class F Shares and would have differed only to the extent that Class Y Shares have lower total annual fund operating expenses than Class F Shares.

XML

Label	Element	Value
Risk/Return:	rr_RiskReturnAbstract
Prospectus Date	rr_ProspectusDate	Jan. 31, 2018