Fair Value Measurements - Interest Rate Derivatives (Details) - Designated as Hedging Instrument - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Fixed-to-Floating Interest Rate Swap \| Fair Value Hedging
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair value hedge derivative instrument liabilities at fair value	$ 159	$ 118
Forward Starting Interest Rate Swap \| Cash Flow Hedge
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Cash flow hedge derivative instrument assets at fair value	$ 54	$ 127

Fair value of all asset derivatives designated as cash flow hedging instruments.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4B
-Subparagraph (c)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480434/815-10-50-4B

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+ References

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- Definition

Fair value as of the balance sheet date of all derivative liabilities designated as interest rate fair value hedging instruments.

+ References

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