Securitizations and Financings - Securitization Trusts (Details) - USD ($) $ in Millions	Jun. 30, 2025	Dec. 31, 2024
Variable Interest Entities and Securitizations [Abstract]
Total collateral balances - UPB	$ 757	$ 798
Total certificate balances	732	773
Financial Asset, Past Due
Financing Receivable, Past Due [Line Items]
Unconsolidated securitization trusts	$ 72	$ 81

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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