Fair Value Measurements - Narrative (Details) - Designated as Hedging Instrument - USD ($) $ in Millions	Jun. 30, 2025	Dec. 31, 2024
2023 & 2025 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	$ 25	$ 7
2022 Fixed-to-Floating Interest Rate Swaps \| 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	92	123
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	0
Cash flow hedge derivative instrument liabilities at fair value	$ 0	$ 0

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

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

+ References

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