Change in Parent Ownership (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended				12 Months Ended
	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2013
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Net Income Attributable to Microchip Technology stockholders	$ 99,402	$ 86,057	$ 93,641	$ 89,909	$ 369,009	$ 395,281	$ 127,389
Increase in paid-in capital for purchase of additional interests					(591)
Parent [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Net Income Attributable to Microchip Technology stockholders					369,009
Increase in paid-in capital for purchase of additional interests					345
Increase in paid-in capital for converted stock options					1,094
Transfer from noncontrolling interests					1,439
Change from net income attributable to Microchip Technology stockholders and transfers from noncontrolling interests					$ 370,448