Securitizations and Variable Interest Entities - Schedule of Cost and Fair Value of Securities (Details) - USD ($) $ in Millions	Jun. 30, 2025	Dec. 31, 2024
Variable Interest Entity [Line Items]
Amortized Cost	$ 469	$ 460
Fair Value	466	464
Variable Interest Entity, Not Primary Beneficiary
Variable Interest Entity [Line Items]
Fair Value	466	464
Rated notes \| Variable Interest Entity, Not Primary Beneficiary
Variable Interest Entity [Line Items]
Amortized Cost	358	356
Fair Value	359	355
Certificates and other assets \| Variable Interest Entity, Not Primary Beneficiary
Variable Interest Entity [Line Items]
Amortized Cost	111	104
Fair Value	$ 107	$ 109

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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+ Details

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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