Net Income Per Common Share From Continuing Operations Attributable to Microchip Technology Stockholders (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	9 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2016	Dec. 31, 2015
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Net income from continuing operations attributable to Microchip Technology	$ 107,335	$ 61,211	$ 33,684	$ 256,777
Weighted average common shares outstanding	216,210,000	203,294,000	215,360,000	203,267,000
Dilutive effect of stock options and RSUs	4,330,000	3,593,000	4,317,000	3,350,000
Dilutive effect of 2037 junior subordinated convertible debentures		11,088,239		10,663,468
Weighted average common and potential common shares outstanding	235,424,000	217,975,000	233,351,000	217,280,000
Income from continuing operations, per basic share (in USD per share)	$ 0.50	$ 0.30	$ 0.16	$ 1.26
Income from continuing operations, per diluted share (in USD per share)	$ 0.46	$ 0.28	$ 0.14	$ 1.18
Antidilutive securities excluded from computation of earnings per share, amount		292,327		319,981
Junior Subordinated Convertible Debentures Due 2037
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Dilutive effect of 2037 junior subordinated convertible debentures	14,883,643		13,673,578
Interest rate of subordinated convertible debentures	2.125%		2.125%
Weighted average conversion price per share used in calculating dilutive effect of convertible debt (amount per share)	$ 23.93	$ 24.62	$ 24.08	$ 24.83
Senior Subordinated Convertible Debenture Due 2025
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Interest rate of subordinated convertible debentures	1.625%		1.625%
Weighted average conversion price per share used in calculating dilutive effect of convertible debt (amount per share)	$ 65.00	$ 66.89	$ 65.40	$ 67.46

The weighted average price per share of the conversion feature embedded in the debt instrument.

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