Securitizations and Financings - Securitization Trusts (Details) - USD ($) $ in Millions	Sep. 30, 2024	Dec. 31, 2023
Variable Interest Entities and Securitizations [Abstract]
Total collateral balances - UPB	$ 819	$ 881
Total certificate balances	793	849
Financial Asset, Past Due
Financing Receivable, Past Due [Line Items]
Unconsolidated securitization trusts	$ 81	$ 91

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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