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

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Amount of liability hedged in fair value hedging relationship.

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Debt and Credit Agreements - Schedule of Interest Rate Derivatives (Details) - USD ($)	Dec. 31, 2022	Mar. 31, 2022	Dec. 31, 2021
Debt Instrument [Line Items]
Debt issued			$ 0
Fixed-to-Floating Interest Rate Swap \| Fair Value Hedging \| Designated as Hedging Instrument
Debt Instrument [Line Items]
Hedged Liability, Fair Value Hedge, Cumulative Increase (Decrease)	$ (118,000,000)
Hedged Liability, Fair Value Hedge	682,000,000
Fixed Rate Notes Due Between 2036 and 2040
Debt Instrument [Line Items]
Debt issued	$ 800,000,000	$ 800,000,000