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Fair Value Measurements - Narrative (Details) - USD ($) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2023 | Dec. 31, 2022
Interest Rate Swap | Cash Flow Hedging | Designated as Hedging Instrument |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Interest rate fair value hedge asset at fair value | $ 48 | $ 127
Fixed-to-Floating Interest Rate Swaps | Fair Value Hedging | Designated as Hedging Instrument |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Interest rate fair value hedge liability at fair value | 107 | $ 118
2023 Fixed-to-Floating Interest Rate Swaps | Fair Value Hedging | Designated as Hedging Instrument |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Interest rate fair value hedge asset at fair value | $ 19 |
Partnerships |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Net asset value, redemption restriction period | 15 days |
Commingled and Common Collective Trust Funds |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Net asset value, redemption restriction period | 45 days |

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