Stockholders' Equity - Schedule of Changes in the Components of AOCI (Details) - USD ($) $ in Millions	12 Months Ended
	Mar. 31, 2025	Mar. 31, 2024	Mar. 31, 2023
Changes in the components of AOCI
Beginning balance	$ 6,657.8	$ 6,513.6	$ 5,894.8
Net other comprehensive income	1.8	0.6	16.5
Ending balance	7,078.3	6,657.8	6,513.6
Total
Changes in the components of AOCI
Beginning balance	(3.5)	(4.1)	(20.6)
Net other comprehensive income	1.8	0.6	16.5
Ending balance	(1.7)	(3.5)	(4.1)
Minimum Pension Liability
Changes in the components of AOCI
Beginning balance	11.6	11.0
Net other comprehensive income	1.8	0.6
Ending balance	13.4	11.6	11.0
Foreign Currency
Changes in the components of AOCI
Beginning balance	(15.1)	(15.1)
Net other comprehensive income	0.0	0.0
Ending balance	$ (15.1)	$ (15.1)	$ (15.1)

Amount of equity (deficit) attributable to parent. Excludes temporary equity and equity attributable to noncontrolling interest.

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MICROCHIP TECHNOLOGY INC 10-K