Derivative Instruments - Effect of Fair Value Hedge Accounting (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Derivative [Line Items]
Mortgage loans	$ 152,149	$ 144,152	$ 133,234
Interest Expense: Long-Term Debt	(129,425)	(121,223)	$ (110,269)
Interest Rate Risk On Held-for-Investment Mortgage Loan \| Interest Income
Derivative [Line Items]
Net impact of hedged mortgage assets and debt	441	(675)
Discontinued hedge-related basis adjustment amortization	31	33
Derivatives designated as hedging instruments	(364)	636
Interest accruals on derivative hedging instruments	217	315
Gains (losses) recognized in net interest income on fair value hedging relationships	325	309
Interest Rate Risk On Debt \| Interest Expense
Derivative [Line Items]
Net impact of hedged mortgage assets and debt	(233)	502
Discontinued hedge-related basis adjustment amortization	(802)	(863)
Derivatives designated as hedging instruments	224	(363)
Interest accruals on derivative hedging instruments	(91)	(425)
Gains (losses) recognized in net interest income on fair value hedging relationships	$ (902)	$ (1,149)

Discontinued hedge related basis adjustment amortization

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- Definition

Interest Accruals On Hedging Instruments

+ References

No definition available.

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- Definition

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.

+ References

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-Topic 815
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- Definition

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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- Definition

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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Total amount of gain (loss) derived from fair value hedges recognized in earnings in the period.

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- Definition

The aggregate interest and fee income generated by: (1) loans the Entity has positive intent and ability to hold for the foreseeable future, or until maturity or payoff, including commercial and consumer loans, whether domestic or foreign, which may consist of: (a) industrial and agricultural; (b) real estate; and (c) real estate construction loans; (d) trade financing; (e) lease financing; (f) home equity lines-of-credit; (g) automobile and other vehicle loans; and (h) credit card and other revolving-type loans and (2) loans and leases held-for-sale which may include mortgage loans, direct financing, and sales-type leases.

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Aggregate amount of interest paid or due on all long-term debt.

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