Basis of Presentation (Details)	Dec. 31, 2011
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Percentage Of Outstanding Stock Of All Subsidiaries Owned	100.00%

The percentage of ownership of common stock or equity participation in the investee.

No definition available.

Name:	mchp_PercentageOfOutstandingStockOfAllSubsidiariesOwned
Namespace Prefix:	mchp_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant