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

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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- Definition

Period when redemption restriction has been in effect for investments for which net asset value per share is calculated (including by unit, membership interest, or other equity (ownership interest) unit measure), in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6A
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-6A

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- Definition

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

+ References

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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- Definition

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

+ References

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