Finance Receivables - Schedule of Credit Risk Profile by Dealer (Details) - Commercial Finance Receivables - USD ($) $ in Millions	Sep. 30, 2026	Dec. 31, 2025
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 18,024	$ 17,365
Dealer Financing
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	16,030	15,211
2026	384	402
2025	302	302
2024	239	157
2023	113	319
2022	267	209
Prior	239	170
Total	$ 17,574	$ 16,769
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	$ 14,334	$ 13,704
2026	350	380
2025	291	221
2024	135	125
2023	89	298
2022	248	160
Prior	209	156
Total	$ 15,657	$ 15,045
Percent	89.10%	89.70%
Dealer Financing \| Group II - Performing accounts experiencing potential weakness in financial metrics
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	$ 1,209	$ 989
2026	21	16
2025	7	33
2024	66	25
2023	22	7
2022	5	35
Prior	24	2
Total	$ 1,355	$ 1,106
Percent	7.70%	6.60%
Dealer Financing \| Group III - Non-Performing accounts with inadequate paying capacity for current obligations
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	$ 488	$ 518
2026	13	5
2025	3	48
2024	38	6
2023	1	14
2022	14	14
Prior	6	12
Total	$ 562	$ 618
Percent	3.20%	3.70%
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	$ 0
2026	0	0
2025	0	0
2024	0	0
2023	0	0
2022	0	0
Prior	0	0
Total	$ 0	$ 0
Percent	0.00%	0.00%

Financing Receivable, Before Allowance For Credit Loss, Percent

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