Loans - Additional Information (Details) $ in Millions	12 Months Ended
Dec. 31, 2025 USD ($) segment	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)
Financing Receivable, Allowance for Credit Loss [Line Items]
Number of portfolio segments \| segment	3
Accrued interest receivable	$ 3,100	$ 2,200
Financing receivable, nonaccrual, interest income	96	111
Net loans held for investment	430,213	311,517
Loans held for sale	760	202
Commercial and multifamily real estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Payment for origination, loan, mortgage, held-for-sale	4,300	3,300	$ 4,400
Federal Home Loan banks
Financing Receivable, Allowance for Credit Loss [Line Items]
Net loans held for investment	6,600	6,700
Remaining borrowing capacity	34,400	35,100
Federal Reserve Discount Window
Financing Receivable, Allowance for Credit Loss [Line Items]
Net loans held for investment	91,600	80,200
Remaining borrowing capacity	53,300	46,700
Domestic credit card: \| Domestic Credit Card and Commercial Banking Portfolios
Financing Receivable, Allowance for Credit Loss [Line Items]
Revolving loans converted to term during period	$ 1,400	$ 847

Amount, before allowance for credit loss, of accrued interest on financing receivable.

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