Debt and Credit Agreements - Schedule of Interest Rate Derivatives (Details) - USD ($)	Sep. 30, 2025	Dec. 31, 2024
Five Separate Fixed-to-Floating Interest Rate Swaps \| Fair Value Hedging \| Designated as Hedging Instrument
Derivative [Line Items]
Fair Value Asset Adjustment to Hedged Notes	$ 27,000,000	$ 7,000,000
Fair Value Liability Adjustment to Hedged Notes	(93,000,000)	(123,000,000)
Carrying Amount of Hedged Notes	1,234,000,000	934,000,000
Fixed Rate Notes Due Between 2036 and 2040
Derivative [Line Items]
Notional Value of Hedged Notes	$ 1,300,000,000	$ 1,050,000,000

Face (par) amount of debt instrument at time of issuance.

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