CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (unaudited) - USD ($) shares in Thousands, $ in Thousands		3 Months Ended		9 Months Ended
		Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2016	Dec. 31, 2015
Income Statement [Abstract]
Net sales		$ 834,366	$ 540,344	$ 2,505,141	$ 1,615,687
Cost of sales (1)	[1]	369,107	247,626	1,280,771	713,002
Gross profit		465,259	292,718	1,224,370	902,685
Research and development (1)	[1]	132,433	97,022	418,111	276,958
Selling, general and administrative (1)	[1]	111,017	76,270	388,651	223,377
Amortization of acquired intangible assets		82,791	48,312	243,356	126,764
Special charges (income) and other, net		20,944	(5,018)	52,522	3,187
Operating expenses		347,185	216,586	1,102,640	630,286
Operating income		118,074	76,132	121,730	272,399
Losses on equity method investments		(55)	(56)	(167)	(289)
Other income (expense):
Interest income		501	6,677	1,765	18,610
Interest expense		(35,143)	(27,507)	(104,685)	(77,203)
Other income (loss), net		121	(5,088)	(658)	10,163
Income before income taxes		83,498	50,158	17,985	223,680
Income tax benefit		(23,837)	(11,053)	(15,699)	(32,890)
Net income from continuing operations		107,335	61,211	33,684	256,570
Loss from discontinued operations		(191)	0	(7,514)	0
Income tax benefit		(31)	0	(1,561)	0
Net loss from discontinued operations		(160)	0	(5,953)	0
Net income		107,175	61,211	27,731	256,570
Less: Net loss attributable to noncontrolling interests		0	0	0	207
Net income attributable to Microchip Technology		$ 107,175	$ 61,211	$ 27,731	$ 256,777
Basic net income from continuing operations, per common share (in USD per share)		$ 0.50	$ 0.30	$ 0.16	$ 1.26
Basic net loss from discontinued operations, per common share (in USD per share)		0.00	0.00	(0.03)	0.00
Basic net income attributable to Microchip Technology, per common share (in USD per share)		0.50	0.30	0.13	1.26
Diluted net income from continuing operations, per common share (in USD per share)		0.46	0.28	0.14	1.18
Diluted net loss from discontinued operations, per common share (in USD per share)		0.00	0.00	(0.02)	0.00
Diluted net income attributable to Microchip Technology, per common share (in USD per share)		0.46	0.28	0.12	1.18
Dividends declared per common share (in USD per share)		$ 0.3605	$ 0.3585	$ 1.0800	$ 1.0740
Basic common shares outstanding		216,210	203,294	215,360	203,267
Diluted common shares outstanding		235,424	217,975	233,351	217,280

[1] Includes share-based compensation expense as follows:Cost of sales 4,100 2,398 11,997 4,055 Research and development 10,171 8,670 27,688 15,768 Selling, general and administrative 10,119 11,958 44,284 17,315