Loans - Additional Information (Details) $ in Millions	12 Months Ended
Dec. 31, 2024 USD ($) segment	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
Financing Receivable, Allowance for Credit Loss [Line Items]
Number of portfolio segments \| segment	3
Accrued interest receivable	$ 2,200	$ 2,200
Net loans held for investment	311,517	305,176
Loans held for sale	$ 202	854
Financing Receivable, Pledged Status [Extensible Enumeration]	Asset Pledged as Collateral [Member]
Commercial and multifamily real estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Payment for origination, loan, mortgage, held-for-sale	$ 3,300	4,400	$ 8,600
Federal Home Loan banks
Financing Receivable, Allowance for Credit Loss [Line Items]
Net loans held for investment	6,700	7,400
Remaining borrowing capacity	35,100	32,100
Federal Reserve Discount Window
Financing Receivable, Allowance for Credit Loss [Line Items]
Net loans held for investment	80,200	78,300
Remaining borrowing capacity	46,700	41,400
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	$ 847	$ 617

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

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