Fair Value Measurements - Interest Rate Derivatives (Details) - Designated as Hedging Instrument - USD ($) $ in Millions	Sep. 30, 2024	Dec. 31, 2023
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	$ 21	$ 19
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	99	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	0	$ 48
Cash flow hedge derivative instrument liabilities at fair value	$ 0

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

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

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