Hedging Activities - Narrative (Details) $ in Millions	3 Months Ended
	Jun. 30, 2025 USD ($)	Jun. 30, 2024 USD ($)	Jun. 30, 2025 CAD ($)	Jun. 30, 2025 USD ($)	Mar. 31, 2025 CAD ($)
Derivative [Line Items]
Other comprehensive income (loss), cash flows hedge, gain (loss) reclassification, before tax	$ 0	$ 0
Currency swap | Cash Flow Hedges | Derivatives designated for hedge accounting
Derivative [Line Items]
Other comprehensive income (loss), cash flows hedge, gain (loss) reclassification, before tax	5,000,000	$ 0
Floating interest rate swaps | Cash Flow Hedges | Derivatives designated for hedge accounting
Derivative [Line Items]
Notional amounts of derivative				$ 1,400,000,000
Derivative, notional amount, entered into during period	$ 550,000,000
CAD | Currency swap | Net Investment Hedging | Derivatives designated for hedge accounting
Derivative [Line Items]
Notional amounts of derivative			$ 6,500		$ 6,500