Restructuring and Other - Schedule of Changes in Restructuring and Other Severance Liability (Details) - USD ($) $ in Millions	6 Months Ended
Sep. 30, 2025	Sep. 30, 2024
Severance liability
Restructuring Incurred Cost Statement Of Income Or Comprehensive Income Extensible Enumeration Not Disclosed	Accruals	Accruals
Severance liability
Severance liability
Beginning balance	$ 23.6	$ 19.4
Accruals	13.9	0.1
Severance payments	(19.6)	(12.1)
Ending balance	$ 17.9	$ 7.4

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- Definition

Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

+ References

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- Definition

Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

+ References

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- Definition

Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

+ References

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

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