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Fair Value Measurements - Interest Rate Derivatives (Details) - Designated as Hedging Instrument - USD ($) $ in Millions | Jun. 30, 2024 | Dec. 31, 2023
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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 | $ 9 | $ 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 | 125 | 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 |

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