v3.26.1
Loans and Related Allowance for Credit Losses, Credit Quality Indicators for Auto Loans by Vintage (Details) - Total Consumer [Member] - USD ($)
$ in Millions
 3 Months Ended 12 Months Ended
Mar. 31, 2026
Mar. 31, 2025
Dec. 31, 2025
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]      
Total loans $ 387,147   $ 386,272
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract]      
Loan charge-offs, loans 997 $ 1,022  
Auto [Member]      
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]      
Term loans by origination year, current fiscal year, finance receivable 9,422   26,538
Term loans by origination year, fiscal year before current fiscal year, finance receivable 24,063   9,059
Term loans by origination year, two years before current fiscal year, finance receivable 8,060   5,625
Term loans by origination year, three years before current fiscal year, finance receivable 4,869   4,931
Term loans by origination year, four years before current fiscal year, finance receivable 4,137   3,602
Term loans by origination year, more than five years before current fiscal year, finance receivable 3,243   732
Total loans 53,794   50,487
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract]      
Term loans by origination year, current fiscal year, charge-offs 1   29
Term loans by origination year, fiscal year before current fiscal year, charge-offs 36   41
Term loans by origination year, two years before current fiscal year, charge-offs 12   47
Term loans by origination year, three years before current fiscal year, charge-offs 10   160
Term loans by origination year, four years before current fiscal year, charge-offs 29   149
Term loans by origination year, more than five years before current fiscal year, charge-offs 26   27
Loan charge-offs, loans 114 $ 127 453
Auto [Member] | FICO 740 or more [Member]      
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]      
Term loans by origination year, current fiscal year, finance receivable 4,954   14,805
Term loans by origination year, fiscal year before current fiscal year, finance receivable 13,060   5,654
Term loans by origination year, two years before current fiscal year, finance receivable 5,005   3,708
Term loans by origination year, three years before current fiscal year, finance receivable 3,178   2,429
Term loans by origination year, four years before current fiscal year, finance receivable 2,025   1,430
Term loans by origination year, more than five years before current fiscal year, finance receivable 1,207   219
Total loans 29,429   28,245
Auto [Member] | FICO 700 to 739 [Member]      
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]      
Term loans by origination year, current fiscal year, finance receivable 1,537   4,376
Term loans by origination year, fiscal year before current fiscal year, finance receivable 3,842   1,419
Term loans by origination year, two years before current fiscal year, finance receivable 1,233   749
Term loans by origination year, three years before current fiscal year, finance receivable 640   630
Term loans by origination year, four years before current fiscal year, finance receivable 516   443
Term loans by origination year, more than five years before current fiscal year, finance receivable 390   87
Total loans 8,158   7,704
Auto [Member] | FICO 660 to 699 [Member]      
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]      
Term loans by origination year, current fiscal year, finance receivable 1,273   3,411
Term loans by origination year, fiscal year before current fiscal year, finance receivable 3,080   1,003
Term loans by origination year, two years before current fiscal year, finance receivable 894   507
Term loans by origination year, three years before current fiscal year, finance receivable 436   534
Term loans by origination year, four years before current fiscal year, finance receivable 443   409
Term loans by origination year, more than five years before current fiscal year, finance receivable 364   87
Total loans 6,490   5,951
Auto [Member] | FICO 620 to 659 [Member]      
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]      
Term loans by origination year, current fiscal year, finance receivable 875   2,039
Term loans by origination year, fiscal year before current fiscal year, finance receivable 1,889   460
Term loans by origination year, two years before current fiscal year, finance receivable 406   248
Term loans by origination year, three years before current fiscal year, finance receivable 218   370
Term loans by origination year, four years before current fiscal year, finance receivable 308   314
Term loans by origination year, more than five years before current fiscal year, finance receivable 288   72
Total loans 3,984   3,503
Auto [Member] | FICO less than 620 [Member]      
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]      
Term loans by origination year, current fiscal year, finance receivable 779   1,892
Term loans by origination year, fiscal year before current fiscal year, finance receivable 2,128   504
Term loans by origination year, two years before current fiscal year, finance receivable 501   410
Term loans by origination year, three years before current fiscal year, finance receivable 381   950
Term loans by origination year, four years before current fiscal year, finance receivable 822   983
Term loans by origination year, more than five years before current fiscal year, finance receivable 964   258
Total loans 5,575   4,997
Auto [Member] | No FICO available [Member]      
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]      
Term loans by origination year, current fiscal year, finance receivable 4   15
Term loans by origination year, fiscal year before current fiscal year, finance receivable 64   19
Term loans by origination year, two years before current fiscal year, finance receivable 21   3
Term loans by origination year, three years before current fiscal year, finance receivable 16   18
Term loans by origination year, four years before current fiscal year, finance receivable 23   23
Term loans by origination year, more than five years before current fiscal year, finance receivable 30   9
Total loans 158   87
Auto [Member] | Current-29 days past due [Member]      
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]      
Term loans by origination year, current fiscal year, finance receivable 9,413   26,413
Term loans by origination year, fiscal year before current fiscal year, finance receivable 23,891   8,993
Term loans by origination year, two years before current fiscal year, finance receivable 7,999   5,560
Term loans by origination year, three years before current fiscal year, finance receivable 4,812   4,728
Term loans by origination year, four years before current fiscal year, finance receivable 3,979   3,357
Term loans by origination year, more than five years before current fiscal year, finance receivable 3,024   654
Total loans 53,118   49,705
Auto [Member] | 30 to 89 days past due [Member]      
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]      
Term loans by origination year, current fiscal year, finance receivable 9   115
Term loans by origination year, fiscal year before current fiscal year, finance receivable 160   61
Term loans by origination year, two years before current fiscal year, finance receivable 56   60
Term loans by origination year, three years before current fiscal year, finance receivable 52   187
Term loans by origination year, four years before current fiscal year, finance receivable 147   227
Term loans by origination year, more than five years before current fiscal year, finance receivable 204   72
Total loans 628   722
Auto [Member] | 90 days or more past due [Member]      
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]      
Term loans by origination year, current fiscal year, finance receivable 0   10
Term loans by origination year, fiscal year before current fiscal year, finance receivable 12   5
Term loans by origination year, two years before current fiscal year, finance receivable 5   5
Term loans by origination year, three years before current fiscal year, finance receivable 5   16
Term loans by origination year, four years before current fiscal year, finance receivable 11   18
Term loans by origination year, more than five years before current fiscal year, finance receivable 15   6
Total loans $ 48   $ 60