Finance Receivables - Schedule of Finance Charges on Consumer Loans (Details) - Nonperforming Financial Instruments - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025
Personal Loans
Financing Receivable, Modified [Line Items]
Net accrued finance charges reversed	$ 45	$ 42	$ 132	$ 120
Finance charges recognized from the contractual interest portion of payments received on nonaccrual loans	5	5	17	15
Auto Finance
Financing Receivable, Modified [Line Items]
Net accrued finance charges reversed	4	3	10	8
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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