Represents the aggregate of expected contributions by employer in the current fiscal year.

No definition available.

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Namespace Prefix:	mchp_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The total amount of expected net periodic benefit cost for defined benefit plans for the current fiscal year. Period benefit costs include the following components: service cost, interest cost, prior service cost or credit, actuarial gain (loss), gain (loss) due to settlements or curtailments.

+ References

No definition available.

+ Details

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Namespace Prefix:	mchp_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Termination Benefits, Salary Period

+ References

No definition available.

+ Details

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Namespace Prefix:	mchp_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of payment to participant of defined benefit plan which decreases benefit obligation. For pension plan, payment includes, but is not limited to, pension benefits and death benefits. For other postretirement plan, payment includes, but is not limited to, prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 60
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=6414203&loc=d3e39716-114964

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)(6)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

+ Details

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

- Details

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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:
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Pension Plans (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
Pension Plans (Narrative) (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2017	Dec. 31, 2016
Defined Benefit Plan Disclosure [Line Items]
Expected periodic pension cost in current fiscal year			$ 3.3
Benefits paid	$ 0.3	$ 0.1	0.6	$ 0.3
Defined benefit plan expected contributions in current fiscal year			$ 0.7
FRANCE \| Minimum
Defined Benefit Plan Disclosure [Line Items]
Termination benefits, salary period (in months)			1 month
FRANCE \| Maximum
Defined Benefit Plan Disclosure [Line Items]
Termination benefits, salary period (in months)			5 months