Finance Receivables - Schedule of Credit Risk Profile by Dealer (Details) - Commercial Finance Receivables - USD ($) $ in Millions	Sep. 30, 2025	Dec. 31, 2024
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 17,081	$ 19,901
Dealer Financing
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	15,032	17,356
2025	290	360
2024	313	225
2023	178	385
2022	339	263
2021	228	269
Prior	231	44
Total	$ 16,611	$ 18,902
Percent	100.00%	100.00%
Dealer Financing \| Group I - Performing accounts with strong to acceptable financial metrics
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	$ 13,511	$ 16,429
2025	272	350
2024	245	211
2023	140	360
2022	315	237
2021	176	267
Prior	214	32
Total	$ 14,873	$ 17,885
Percent	89.50%	94.60%
Dealer Financing \| Group II - Performing accounts experiencing potential weakness in financial metrics
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	$ 973	$ 621
2025	12	0
2024	27	10
2023	28	26
2022	9	3
2021	35	2
Prior	2	0
Total	$ 1,087	$ 663
Percent	6.50%	3.50%
Dealer Financing \| Group III - Non-Performing accounts with inadequate paying capacity for current obligations
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	$ 547	$ 305
2025	6	10
2024	41	4
2023	10	0
2022	14	22
2021	17	0
Prior	15	12
Total	$ 651	$ 354
Percent	3.90%	1.90%
Dealer Financing \| Group IV - Non-Performing accounts with inadequate paying capacity for current obligations and inherent weaknesses
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	$ 0	$ 1
2025	0	0
2024	0	0
2023	0	0
2022	0	0
2021	0	0
Prior	0	0
Total	$ 0	$ 1
Percent	0.00%	0.00%

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