Commitments and Contingencies - Additional Information (Detail) - USD ($)	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021
Loss Contingencies [Line Items]
Fair value	$ 9,060,000,000	$ 5,780,000,000
Loans pledged to FHLB, collateral for wholesale borrowings	44,500,000,000	33,900,000,000
Commitments	22,368,000,000
Commitments to purchase securities	0
Asset pledged as collateral
Loss Contingencies [Line Items]
Fair value	4,000,000	464,000,000
Mortgage-Related Securities
Loss Contingencies [Line Items]
Securities held to maturity, mortgaged related securities, pledged	430,000,000	704,000,000
Total loan commitments
Loss Contingencies [Line Items]
Commitments	21,827,000,000	2,800,000,000
Commercial, performance stand-by, and financial stand-by letters of credit
Loss Contingencies [Line Items]
Commitments	$ 541,000,000	$ 291,000,000

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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