Special Charges and Other, Net - Summary of Activity in Special Charges and Other, Net (Details) - USD ($) $ in Millions	12 Months Ended
Mar. 31, 2022	Mar. 31, 2021	Mar. 31, 2020
Restructuring
Employee separation costs	$ 0.6	$ (1.3)	$ 6.0
Gain on sale of assets	(7.9)	(5.8)	(1.5)
Impairment charges	0.0	0.0	0.7
Contract exit costs	5.0	(1.6)	5.2
Wafer fabrication restructuring	21.1	15.0	18.0
Other	(0.3)	0.1	2.6
Legal contingencies	12.5	0.2	15.7
Contingent consideration revaluation	(1.5)	(4.9)	0.0
Total	$ 29.5	$ 1.7	$ 46.7

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Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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Amount of expenses for special or contractual termination benefits provided to current employees involuntarily terminated under a benefit arrangement associated exit or disposal activities pursuant to an authorized plan. Excludes expenses related to one-time termination benefits, a discontinued operation or an asset retirement obligation.

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