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Investment Securities - Additional Information (Details) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024
Debt Securities, Available-for-sale [Line Items]
Accrued interest receivable	$ 327	$ 262
Investment securities	39,700	39,400
Securities received as collateral	$ 1	$ 18
Investment securities available for sale | Government Contracts Concentration Risk | US Treasury and Agency securities
Debt Securities, Available-for-sale [Line Items]
Percentage of portfolio	97.00%	96.00%

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Amount of interest income on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), from change in present value of expected cash flows, attributable to passage of time.

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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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