Comprehensive Income (Schedule Of Reclassifications Of Recognized Transactions Out Of AOCI) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other income, net									$ 8,864	$ 13,742	$ 5,898
Income tax provision									42,632	19,418	(37,073)
Net income attributable to Microchip Technology	$ 67,355	$ 61,211	$ 64,899	$ 130,667	$ 99,402	$ 86,057	$ 93,641	$ 89,909	324,132	369,009	395,281
Reclassification out of Accumulated Other Comprehensive Income [Member] | Accumulated Net Unrealized Investment Gain (Loss) [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other income, net									10,948	18,706	2,371
Income tax provision									0	(12)	(776)
Net income attributable to Microchip Technology									$ 10,948	$ 18,694	$ 1,595