Borrowings - Additional Information (Details) - USD ($)	Sep. 30, 2023	Dec. 31, 2022
Debt Instrument [Line Items]
FHLB advances maximum amount available	$ 4,400,000,000	$ 3,300,000,000
Federal Home Loan Bank Advances And Letters Of Credit Amount Used	400,000,000	800,000,000
Assets sold under agreements to repurchase	93,071,000	148,609,000
Other short-term borrowings	0	365,000,000
Advances with FRB
Debt Instrument [Line Items]
Line Of Credit Facility Current Borrowing Capacity	4,600,000,000	1,400,000,000
Federal Home Loan Bank
Debt Instrument [Line Items]
Line Of Credit Facility Capacity Available For Specific Purpose Other Than For Trade Purchases	300,000,000	400,000,000
Other short-term borrowings	$ 0	$ 365,000,000