The percentage of the Company's transactions that are denominated in U.S. dollars.

No definition available.

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

- Definition

Nominal or face amount used to calculate payments on the derivative asset.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5579245-113959

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
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-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5580258-113959

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5579245-113959

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5618551-113959

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount before tax of foreign currency transaction realized and unrealized gain (loss) recognized in the income statement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 830
-SubTopic 20
-Section 50
-Paragraph 1
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+ Details

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

- Definition

Number of foreign currency exchange rate derivatives held by the entity at the reporting date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
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+ Details

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Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Details

Name:	us-gaap_IncomeStatementLocationAxis=us-gaap_OtherNonoperatingIncomeExpenseMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_HedgingDesignationAxis=us-gaap_NondesignatedMember
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Data Type:	na
Balance Type:
Period Type:

- Details

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Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_CurrencyAxis=currency_MYR
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Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_HedgingDesignationAxis=us-gaap_DesignatedAsHedgingInstrumentMember
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Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_CurrencyAxis=currency_TWD
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Derivative Instruments (Details) $ in Millions	3 Months Ended		6 Months Ended
Derivative Instruments (Details) $ in Millions	Sep. 30, 2019 USD ($) contract	Sep. 30, 2018 USD ($)	Sep. 30, 2019 USD ($) contract	Sep. 30, 2018 USD ($)	Mar. 31, 2019 contract
Derivative [Line Items]
Percentage of company sales denominated in US dollars			99.00%
Foreign currency transaction losses, before tax	$ 2.8	$ 0.0	$ 0.3	$ 4.4
Number of foreign currency derivatives held (in contracts) \| contract	1		1		0
Other income (loss), net \| Not designated as hedging instrument \| Foreign exchange forward contract
Derivative [Line Items]
Gain (loss) on foreign currency derivatives	$ 0.0	$ 0.0	$ 0.0	$ 0.0
Malaysia, Ringgits \| Designated as hedging \| Foreign exchange forward contract
Derivative [Line Items]
Outstanding forward contract liability	250.0		250.0
Taiwan, New Dollars \| Designated as hedging \| Foreign exchange forward contract
Derivative [Line Items]
Outstanding forward contract liability	$ 30.1		$ 30.1