Finance Receivables - Schedule of Credit Risk Profile by Dealer (Details) - Commercial Finance Receivables - USD ($) $ in Millions	Jun. 30, 2025	Dec. 31, 2024
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 16,723	$ 19,901
Dealer Financing
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	14,586	17,356
2025	181	360
2024	329	225
2023	192	385
2022	359	263
2021	243	269
Prior	263	44
Total	$ 16,152	$ 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	$ 13,089	$ 16,429
2025	167	350
2024	252	211
2023	159	360
2022	331	237
2021	184	267
Prior	242	32
Total	$ 14,423	$ 17,885
Percent	89.30%	94.60%
Dealer Financing \| Group II - Performing accounts experiencing potential weakness in financial metrics
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	$ 910	$ 621
2025	10	0
2024	27	10
2023	29	26
2022	14	3
2021	36	2
Prior	5	0
Total	$ 1,031	$ 663
Percent	6.40%	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	$ 587	$ 305
2025	4	10
2024	50	4
2023	5	0
2022	14	22
2021	23	0
Prior	15	12
Total	$ 699	$ 354
Percent	4.30%	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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