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Finance Receivables and Loans, Net - Schedule of Financing Receivable Credit Quality Indicators Consumer (Details) - USD ($) $ in Millions | Sep. 30, 2025 | Dec. 31, 2024
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Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total finance receivables and loans | $ 134,567 | $ 136,030
Consumer |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total finance receivables and loans | 101,247 | 103,285
Consumer | Consumer automotive, excludes basis adjustment |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Year one, originated, current fiscal year | 26,611 | 30,919
Year two, originated, fiscal year before current fiscal year | 23,225 | 21,604
Year three, originated, two years before current fiscal year | 15,513 | 16,607
Year four, originated, three years before current fiscal year | 11,353 | 9,247
Year five, originated, four years before current fiscal year | 5,750 | 3,344
Originated, more than five years before current fiscal year | 2,544 | 2,077
Revolving loans | 0 | 0
Revolving loans converted to term | 0 | 0
Total finance receivables and loans | 84,996 | 83,798
Consumer | Consumer mortgage finance receivables |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Year one, originated, current fiscal year | 0 | 13
Year two, originated, fiscal year before current fiscal year | 18 | 33
Year three, originated, two years before current fiscal year | 31 | 1,914
Year four, originated, three years before current fiscal year | 1,811 | 9,856
Year five, originated, four years before current fiscal year | 9,421 | 1,721
Originated, more than five years before current fiscal year | 4,861 | 3,564
Revolving loans | 99 | 116
Revolving loans converted to term | 12 | 17
Total finance receivables and loans | 16,253 | 17,234
Consumer | Other |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Year one, originated, current fiscal year |  | 0
Year two, originated, fiscal year before current fiscal year |  | 0
Year three, originated, two years before current fiscal year |  | 0
Year four, originated, three years before current fiscal year |  | 0
Year five, originated, four years before current fiscal year |  | 0
Originated, more than five years before current fiscal year |  | 0
Revolving loans |  | 2,294
Revolving loans converted to term |  | 0
Total finance receivables and loans | 0 | 2,294
Consumer | Automotive |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total finance receivables and loans | 84,994 | 83,757
Liability excluded from amortized cost of hedged asset, portfolio layer method | 2 | 41
Consumer Portfolio Segment, Excludes Basis Adjustment for Automotive Loans |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Year one, originated, current fiscal year | 26,611 | 30,932
Year two, originated, fiscal year before current fiscal year | 23,243 | 21,637
Year three, originated, two years before current fiscal year | 15,544 | 18,521
Year four, originated, three years before current fiscal year | 13,164 | 19,103
Year five, originated, four years before current fiscal year | 15,171 | 5,065
Originated, more than five years before current fiscal year | 7,405 | 5,641
Revolving loans | 99 | 2,410
Revolving loans converted to term | 12 | 17
Total finance receivables and loans | 101,249 | 103,326
Current | Consumer | Consumer automotive, excludes basis adjustment |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Year one, originated, current fiscal year | 26,219 | 30,322
Year two, originated, fiscal year before current fiscal year | 22,326 | 20,387
Year three, originated, two years before current fiscal year | 14,493 | 15,234
Year four, originated, three years before current fiscal year | 10,345 | 8,368
Year five, originated, four years before current fiscal year | 5,166 | 3,064
Originated, more than five years before current fiscal year | 2,281 | 1,849
Revolving loans | 0 | 0
Revolving loans converted to term | 0 | 0
Total finance receivables and loans | 80,830 | 79,224
Current | Consumer | Consumer mortgage finance receivables |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Year one, originated, current fiscal year | 0 | 13
Year two, originated, fiscal year before current fiscal year | 18 | 31
Year three, originated, two years before current fiscal year | 31 | 1,901
Year four, originated, three years before current fiscal year | 1,791 | 9,834
Year five, originated, four years before current fiscal year | 9,376 | 1,714
Originated, more than five years before current fiscal year | 4,803 | 3,503
Revolving loans | 97 | 115
Revolving loans converted to term | 10 | 15
Total finance receivables and loans | 16,126 | 17,126
Current | Consumer | Other |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Year one, originated, current fiscal year |  | 0
Year two, originated, fiscal year before current fiscal year |  | 0
Year three, originated, two years before current fiscal year |  | 0
Year four, originated, three years before current fiscal year |  | 0
Year five, originated, four years before current fiscal year |  | 0
Originated, more than five years before current fiscal year |  | 0
Revolving loans |  | 2,140
Revolving loans converted to term |  | 0
Total finance receivables and loans |  | 2,140
30–59 days past due | Consumer | Consumer automotive, excludes basis adjustment |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Year one, originated, current fiscal year | 284 | 419
Year two, originated, fiscal year before current fiscal year | 578 | 756
Year three, originated, two years before current fiscal year | 633 | 841
Year four, originated, three years before current fiscal year | 615 | 546
Year five, originated, four years before current fiscal year | 366 | 174
Originated, more than five years before current fiscal year | 162 | 141
Revolving loans | 0 | 0
Revolving loans converted to term | 0 | 0
Total finance receivables and loans | 2,638 | 2,877
30–59 days past due | Consumer | Consumer mortgage finance receivables |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Year one, originated, current fiscal year | 0 | 0
Year two, originated, fiscal year before current fiscal year | 0 | 0
Year three, originated, two years before current fiscal year | 0 | 7
Year four, originated, three years before current fiscal year | 9 | 9
Year five, originated, four years before current fiscal year | 26 | 5
Originated, more than five years before current fiscal year | 24 | 27
Revolving loans | 1 | 0
Revolving loans converted to term | 0 | 0
Total finance receivables and loans | 60 | 48
30–59 days past due | Consumer | Other |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Year one, originated, current fiscal year |  | 0
Year two, originated, fiscal year before current fiscal year |  | 0
Year three, originated, two years before current fiscal year |  | 0
Year four, originated, three years before current fiscal year |  | 0
Year five, originated, four years before current fiscal year |  | 0
Originated, more than five years before current fiscal year |  | 0
Revolving loans |  | 35
Revolving loans converted to term |  | 0
Total finance receivables and loans |  | 35
60–89 days past due | Consumer | Consumer automotive, excludes basis adjustment |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Year one, originated, current fiscal year | 78 | 131
Year two, originated, fiscal year before current fiscal year | 232 | 338
Year three, originated, two years before current fiscal year | 283 | 390
Year four, originated, three years before current fiscal year | 287 | 240
Year five, originated, four years before current fiscal year | 156 | 75
Originated, more than five years before current fiscal year | 68 | 56
Revolving loans | 0 | 0
Revolving loans converted to term | 0 | 0
Total finance receivables and loans | 1,104 | 1,230
60–89 days past due | Consumer | Consumer mortgage finance receivables |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Year one, originated, current fiscal year | 0 | 0
Year two, originated, fiscal year before current fiscal year | 0 | 0
Year three, originated, two years before current fiscal year | 0 | 4
Year four, originated, three years before current fiscal year | 5 | 4
Year five, originated, four years before current fiscal year | 2 | 1
Originated, more than five years before current fiscal year | 5 | 4
Revolving loans | 0 | 0
Revolving loans converted to term | 0 | 0
Total finance receivables and loans | 12 | 13
60–89 days past due | Consumer | Other |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Year one, originated, current fiscal year |  | 0
Year two, originated, fiscal year before current fiscal year |  | 0
Year three, originated, two years before current fiscal year |  | 0
Year four, originated, three years before current fiscal year |  | 0
Year five, originated, four years before current fiscal year |  | 0
Originated, more than five years before current fiscal year |  | 0
Revolving loans |  | 33
Revolving loans converted to term |  | 0
Total finance receivables and loans |  | 33
90 or more days past due | Consumer | Consumer automotive, excludes basis adjustment |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Year one, originated, current fiscal year | 30 | 47
Year two, originated, fiscal year before current fiscal year | 89 | 123
Year three, originated, two years before current fiscal year | 104 | 142
Year four, originated, three years before current fiscal year | 106 | 93
Year five, originated, four years before current fiscal year | 62 | 31
Originated, more than five years before current fiscal year | 33 | 31
Revolving loans | 0 | 0
Revolving loans converted to term | 0 | 0
Total finance receivables and loans | 424 | 467
90 or more days past due | Consumer | Consumer mortgage finance receivables |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Year one, originated, current fiscal year | 0 | 0
Year two, originated, fiscal year before current fiscal year | 0 | 2
Year three, originated, two years before current fiscal year | 0 | 2
Year four, originated, three years before current fiscal year | 6 | 9
Year five, originated, four years before current fiscal year | 17 | 1
Originated, more than five years before current fiscal year | 29 | 30
Revolving loans | 1 | 1
Revolving loans converted to term | 2 | 2
Total finance receivables and loans | $ 55 | 47
90 or more days past due | Consumer | Other |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Year one, originated, current fiscal year |  | 0
Year two, originated, fiscal year before current fiscal year |  | 0
Year three, originated, two years before current fiscal year |  | 0
Year four, originated, three years before current fiscal year |  | 0
Year five, originated, four years before current fiscal year |  | 0
Originated, more than five years before current fiscal year |  | 0
Revolving loans |  | 86
Revolving loans converted to term |  | 0
Total finance receivables and loans |  | $ 86

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