Income Taxes - Summary of Valuation Allowance (Details) - USD ($) $ in Millions	12 Months Ended
	Mar. 31, 2025	Mar. 31, 2024	Mar. 31, 2023
Deferred Tax Asset, Change In Valuation Allowance [Roll Forward]
Beginning balance	$ 341.6	$ 152.2	$ 362.8
Changes in valuation allowance	302.7	4.2	(2.3)
Other	42.3	185.2	(208.3)
Ending balance	686.6	341.6	$ 152.2
eOne
Deferred Tax Asset, Change In Valuation Allowance [Roll Forward]
Other	$ 23.0	$ 187.0