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Hedging Activities - Schedule of Derivative Instruments Gain (Loss) (Details) - USD ($)	12 Months Ended
	Mar. 31, 2026	Mar. 31, 2025	Mar. 31, 2024
Derivatives, Fair Value [Line Items]
Derivatives designated as cash flow and other hedges:		$ 0	$ 0
Derivatives designated for hedge accounting | Net Investment Hedging | Cross-currency swaps
Derivatives, Fair Value [Line Items]
Derivatives designated as net investment hedges:	$ (142,000,000)	80,000,000	3,000,000
Derivatives designated for hedge accounting | Cash Flow Hedging | Cross-currency swaps
Derivatives, Fair Value [Line Items]
Derivatives designated as cash flow and other hedges:	0
Derivatives designated for hedge accounting | Cash Flow Hedging | Foreign currency forwards
Derivatives, Fair Value [Line Items]
Derivatives designated as cash flow and other hedges:	12,000,000		$ 0
Derivatives designated for hedge accounting | Cash Flow Hedging | Fixed interest rate swaps
Derivatives, Fair Value [Line Items]
Derivatives designated as cash flow and other hedges:	$ 0	$ 0

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Amount, before tax, of reclassification of gain (loss) from accumulated other comprehensive income (AOCI) for derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

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