Fair Value Measurements - Interest Rate Derivatives (Details) - Designated as Hedging Instrument - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
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	$ 131	$ 107
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	51	48
Two Separate Fixed-to-Floating Interest Rate Swaps \| Fair Value Hedging
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Interest rate fair value hedge asset at fair value	$ 11	$ 19

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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