Conversion Features (Details) $ / shares in Units, $ in Millions	12 Months Ended
Mar. 31, 2017 USD ($) day $ / shares
2007 Junior Subordinated Convertible Notes
Debt Instrument [Line Items]
Threshold percentage of stock price trigger	130.00%
Contingent interest rate	0.50%
If-converted value in excess of principal \| $	$ 303.1
2015 Senior Subordinated Convertible Debt
Debt Instrument [Line Items]
If-converted value in excess of principal \| $	$ 248.5
Minimum \| 2007 Junior Subordinated Convertible Notes
Debt Instrument [Line Items]
Contingent interest rate	0.25%
Debenture trading price \| $ / shares	$ 400
Maximum \| 2007 Junior Subordinated Convertible Notes
Debt Instrument [Line Items]
Contingent interest rate	0.50%
Debenture trading price \| $ / shares	$ 1,500
Convertible Debt \| Debt Instrument, Redemption, Period One
Debt Instrument [Line Items]
Threshold percentage of stock price trigger	130.00%
Threshold trading days \| day	20
Threshold consecutive trading days	30 days
Convertible Debt \| Debt Instrument, Redemption, Period Two
Debt Instrument [Line Items]
Threshold percentage of stock price trigger	98.00%
Threshold trading days \| day	5
Threshold consecutive trading days	10 days

Debt Instrument, Convertible, Trading Price

No definition available.

Name:	mchp_DebtInstrumentConvertibleTradingPrice
Namespace Prefix:	mchp_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Long-term Debt, Contingent Payment of Interest, Percentage

+ References

No definition available.

+ Details

Name:	mchp_LongtermDebtContingentPaymentofInterestPercentage
Namespace Prefix:	mchp_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The amount by which the convertible debt's if-converted value exceeds its principle amount at the balance sheet date, regardless of whether the instrument is currently convertible. This element applies to public companies only.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6928298&loc=SL6031898-161870

+ Details

Name:	us-gaap_DebtInstrumentConvertibleIfConvertedValueInExcessOfPrincipal
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Threshold period of specified consecutive trading days within which common stock price to conversion price of convertible debt instruments must exceed threshold percentage for a specified number of trading days to trigger conversion feature, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentConvertibleThresholdConsecutiveTradingDays
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Minimum percentage of common stock price to conversion price of convertible debt instruments to determine eligibility of conversion.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentConvertibleThresholdPercentageOfStockPriceTrigger
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Threshold number of specified trading days that common stock price to conversion price of convertible debt instruments must exceed threshold percentage within a specified consecutive trading period to trigger conversion feature.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentConvertibleThresholdTradingDays
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_DebtInstrumentAxis=mchp_A2007JuniorSubordinatedConvertibleNotesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=mchp_A2015SeniorSubordinatedConvertibleDebtMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RangeAxis=us-gaap_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RangeAxis=us-gaap_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_ConvertibleDebtMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentRedemptionPeriodAxis=us-gaap_DebtInstrumentRedemptionPeriodOneMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentRedemptionPeriodAxis=us-gaap_DebtInstrumentRedemptionPeriodTwoMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: