Securitizations and Financings - Securitization Trusts (Details) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Variable Interest Entities and Securitizations [Abstract]
Total collateral balances - UPB	$ 901	$ 976
Total certificate balances	876	949
Financial Asset, Past Due
Financing Receivable, Past Due [Line Items]
Unconsolidated securitization trusts	$ 93	$ 119

Amortized cost, before allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement and net investment in lease.

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+ Details