Master Netting and Similar Agreements—Repurchase, Reverse Repurchase, and Securities Borrowing Transactions - Schedule of the Remaining Contractual Maturity by Collateral Type of Securities Sold Under Agreements To Repurchase (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Securities sold under agreements to repurchase	$ 1,828	$ 1,921
Overnight and Continuous
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Securities sold under agreements to repurchase	1,828	1,921
Up to 30 Days
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Securities sold under agreements to repurchase	0	0
Government agency issued MBS
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Securities sold under agreements to repurchase	1,655	1,717
Government agency issued MBS | Overnight and Continuous
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Securities sold under agreements to repurchase	1,655	1,717
Government agency issued MBS | Up to 30 Days
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Securities sold under agreements to repurchase	0	0
Government agency issued CMO
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Securities sold under agreements to repurchase	118	161
Government agency issued CMO | Overnight and Continuous
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Securities sold under agreements to repurchase	118	161
Government agency issued CMO | Up to 30 Days
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Securities sold under agreements to repurchase	0	0
Other U.S. government agencies
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Securities sold under agreements to repurchase	55	43
Other U.S. government agencies | Overnight and Continuous
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Securities sold under agreements to repurchase	55	43
Other U.S. government agencies | Up to 30 Days
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Securities sold under agreements to repurchase	$ 0	$ 0