Derivative Instruments - Cumulative Basis Adjustments for Fair Value Hedges (Details) - USD ($) $ in Millions	Sep. 30, 2025	Dec. 31, 2024
Derivatives, Fair Value [Line Items]
Amortized cost of the hedged assets	$ 634	$ 484
Amortized cost of the hedged liabilities	(697)	(676)
Cumulative fair value hedging adjustment included in the amortized cost of the hedged assets	27	7
Cumulative fair value hedging adjustment included in the amortized cost of the hedged assets (liabilities)	178	199
Discontinued Hedges
Derivatives, Fair Value [Line Items]
Cumulative fair value hedging adjustment included in the amortized cost of the hedged assets (liabilities)	$ (297)	$ (310)

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.

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Fair value of all derivative assets designated as fair value hedging instruments.

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Amount of cumulative increase (decrease) in fair value of hedged asset in fair value hedge, attributable to hedged risk. Excludes cumulative basis adjustment related to foreign exchange risk.

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Amount of cumulative increase (decrease) in fair value of hedged liability in fair value hedge, attributable to hedged risk. Excludes cumulative basis adjustment related to foreign exchange risk.

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