Net income per common share attributable to Microchip Technology Stockholders (Details) - USD ($) $ / shares in Units, $ 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
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
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
Weighted average common shares outstanding									203,384,000	200,937,000	198,291,000
Dilutive effect of stock options and RSUs									3,350,000	3,642,000	3,910,000
Dilutive effect of 2037 junior subordinated convertible debentures									10,654,070	18,982,440	15,429,003
Weighted average common and potential common shares outstanding									217,388,000	223,561,000	217,630,000
Basic net income per common share attributable to Microchip Technology stockholders									$ 1.59	$ 1.84	$ 1.99
Diluted net income per common share attributable to Microchip Technology stockholders	$ 0.31	$ 0.28	$ 0.30	$ 0.60	$ 0.45	$ 0.39	$ 0.42	$ 0.40	$ 1.49	$ 1.65	$ 1.82
Number of antidilutive option shares (in shares)									298,015	19,305	0
Junior Subordinated Convertible Debentures Due2037 Member
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Weighted Average Conversion Price Per Share Used In Calculating Dilutive Effect Of Convertible Debt Amount Per Share									$ 24.73	$ 25.48	$ 26.32
Senior Subordinated Convertible Debenture Due 2025 [Member]
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Weighted Average Conversion Price Per Share Used In Calculating Dilutive Effect Of Convertible Debt Amount Per Share									$ 67.19	$ 68.25