Derivative Financial Instruments and Hedging Activities (Details) - USD ($)	3 Months Ended
Mar. 31, 2025	Mar. 31, 2024	Dec. 31, 2024
Derivative [Line Items]
Debt Carrying Value Fair Value	$ 43,300,000,000		$ 41,100,000,000
Income Effect of Derivative Financial Instruments [Abstract]
Derivative, Gain (Loss) on Derivative, Net	(11,000,000)	$ (176,000,000)
Balance Sheet Effect of Derivative Financial Instruments [Abstract]
Fair Value of Derivative Assets	951,000,000		784,000,000
Fair Value of Derivative Liabilities	1,391,000,000		1,992,000,000
Derivative, Notional Amount	119,743,000,000		112,144,000,000
Derivative, Collateral, Obligation to Return Cash	26,000,000		27,000,000
Derivative, Collateral, Right to Reclaim Cash	119,000,000		127,000,000
Derivative Asset, Not Offset, Policy Election Deduction	595,000,000		450,000,000
Derivative Liability, Not Offset, Policy Election Deduction	595,000,000		450,000,000
Interest Rate Contract [Member] \| Designated as Hedging Instrument [Member] \| Fair Value Hedging [Member]
Income Effect of Derivative Financial Instruments [Abstract]
Change in Unrealized Gain (Loss) on Fair Value Hedging Instruments	329,000,000	(243,000,000)
Change in Unrealized Gain (Loss) on Hedged Item in Fair Value Hedge	(324,000,000)	220,000,000
Balance Sheet Effect of Derivative Financial Instruments [Abstract]
Derivative, Notional Amount	21,642,000,000		16,194,000,000
Loss from Components Excluded from Assessment of Fair Value Hedge Effectiveness	(48,000,000)	(96,000,000)
Interest Rate Contract [Member] \| Designated as Hedging Instrument [Member] \| Currency Swap
Income Effect of Derivative Financial Instruments [Abstract]
Change in Unrealized Gain (Loss) on Fair Value Hedging Instruments	146,000,000	(64,000,000)
Change in Unrealized Gain (Loss) on Hedged Item in Fair Value Hedge	(136,000,000)	62,000,000
Balance Sheet Effect of Derivative Financial Instruments [Abstract]
Derivative, Notional Amount	3,802,000,000		3,802,000,000
Loss from Components Excluded from Assessment of Fair Value Hedge Effectiveness	(25,000,000)	(29,000,000)
Interest Rate Contract [Member] \| Designated as Hedging Instrument [Member] \| Level 2 [Member] \| Fair Value, Recurring [Member] \| Fair Value Hedging [Member]
Balance Sheet Effect of Derivative Financial Instruments [Abstract]
Fair Value of Derivative Assets	265,000,000		66,000,000
Fair Value of Derivative Liabilities	446,000,000		645,000,000
Interest Rate Contract [Member] \| Designated as Hedging Instrument [Member] \| Level 2 [Member] \| Fair Value, Recurring [Member] \| Currency Swap
Balance Sheet Effect of Derivative Financial Instruments [Abstract]
Fair Value of Derivative Assets	87,000,000		9,000,000
Fair Value of Derivative Liabilities	75,000,000		139,000,000
Interest Rate Contract [Member] \| Not Designated as Hedging Instrument [Member]
Income Effect of Derivative Financial Instruments [Abstract]
Derivative, Gain (Loss) on Derivative, Net	(45,000,000)	48,000,000
Balance Sheet Effect of Derivative Financial Instruments [Abstract]
Derivative, Notional Amount	78,371,000,000		76,977,000,000
Interest Rate Contract [Member] \| Not Designated as Hedging Instrument [Member] \| Level 2 [Member] \| Fair Value, Recurring [Member]
Balance Sheet Effect of Derivative Financial Instruments [Abstract]
Fair Value of Derivative Assets	322,000,000		305,000,000
Fair Value of Derivative Liabilities	752,000,000		845,000,000
Interest Rate Contract [Member] \| Not Designated as Hedging Instrument [Member] \| Level 2 [Member] \| Fair Value, Recurring [Member] \| Affiliated Entity
Balance Sheet Effect of Derivative Financial Instruments [Abstract]
Fair Value of Derivative Assets	115,000,000
Foreign Exchange Contract [Member] \| Not Designated as Hedging Instrument [Member]
Income Effect of Derivative Financial Instruments [Abstract]
Derivative, Gain (Loss) on Derivative, Net	(10,000,000)	92,000,000
Balance Sheet Effect of Derivative Financial Instruments [Abstract]
Derivative, Notional Amount	11,595,000,000		9,716,000,000
Foreign Exchange Contract [Member] \| Not Designated as Hedging Instrument [Member] \| Affiliated Entity
Balance Sheet Effect of Derivative Financial Instruments [Abstract]
Derivative, Notional Amount	6,400,000,000		5,300,000,000
Foreign Exchange Contract [Member] \| Not Designated as Hedging Instrument [Member] \| Level 2 [Member] \| Fair Value, Recurring [Member]
Balance Sheet Effect of Derivative Financial Instruments [Abstract]
Fair Value of Derivative Assets	152,000,000		271,000,000
Fair Value of Derivative Liabilities	46,000,000		117,000,000
Foreign Exchange Contract [Member] \| Not Designated as Hedging Instrument [Member] \| Level 2 [Member] \| Fair Value, Recurring [Member] \| Affiliated Entity
Balance Sheet Effect of Derivative Financial Instruments [Abstract]
Fair Value of Derivative Liabilities	41,000,000
Cross Currency Interest Rate Contract [Member] \| Not Designated as Hedging Instrument [Member]
Income Effect of Derivative Financial Instruments [Abstract]
Derivative, Gain (Loss) on Derivative, Net	102,000,000	$ (166,000,000)
Balance Sheet Effect of Derivative Financial Instruments [Abstract]
Derivative, Notional Amount	4,333,000,000		5,455,000,000
Cross Currency Interest Rate Contract [Member] \| Not Designated as Hedging Instrument [Member] \| Level 2 [Member] \| Fair Value, Recurring [Member]
Balance Sheet Effect of Derivative Financial Instruments [Abstract]
Fair Value of Derivative Assets	125,000,000		133,000,000
Fair Value of Derivative Liabilities	$ 72,000,000		$ 246,000,000

Balance Sheet Effect of Derivative Financial Instruments [Abstract]

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Fair value of hedged debt carried at cost which approximates fair value

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Income Effect of Derivative Financial Instruments [Abstract]

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Amount of gain (loss) from the increase (decrease) in fair value of derivative and nonderivative instruments designated as fair value hedging instruments recognized in the income statement.

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Amount of the increase (decrease) in fair value of the hedged item in a fair value hedge recognized in the income statement.

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Fair value of financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and contract can be net settled by means outside contract or delivery of asset, subject to master netting arrangement or similar agreement and not elected or qualified to offset, deducted from derivative asset.

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Amount of obligation to return cash collateral under master netting arrangements that have not been offset against derivative assets.

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Amount of right to receive cash collateral under master netting arrangements that have not been offset against derivative liabilities.

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Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

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Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

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Nominal or face amount used to calculate payment on derivative.

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Loss relating to components of the gain (loss) on the fair value hedging instrument excluded from the assessment of fair value hedge effectiveness. Recognized in earnings.

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