Finance Receivables - Schedule of Finance Charges on Consumer Loans (Details) - Nonperforming (Nonaccrual) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Personal Loans
Financing Receivable, Modified [Line Items]
Net accrued finance charges reversed	$ 41	$ 37	$ 88	$ 78
Finance charges recognized from the contractual interest portion of payments received on nonaccrual loans	6	5	12	10
Auto Finance
Financing Receivable, Modified [Line Items]
Net accrued finance charges reversed	3	2	7	6
Finance charges recognized from the contractual interest portion of payments received on nonaccrual loans	$ 0	$ 0	$ 1	$ 1

Amount of writeoff of accrued interest on financing receivable recognized by reversing interest income.

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