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Fair Value - Schedule of Fair Value Measurements - Recurring Basis (Details) - USD ($) $ in Millions | Mar. 31, 2025 | Dec. 31, 2024
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Equity securities | $ 942 | $ 871
Total available-for-sale securities | $ 22,346 | $ 22,410
Derivative Asset, Statement of Financial Position [Extensible Enumeration] | Finance receivables and loans, net | Finance receivables and loans, net
Investment in any one industry did not exceed percentage | 11.00% | 14.00%
Carrying amount, equity investments without a readily determinable fair value | $ 93 | $ 91
Fair value, measurements, recurring |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total available-for-sale securities | 22,346 | 22,410
Mortgage loans held-for-sale | 6 | 16
Derivative contracts in a receivable position | 2 | 12
Total assets | 23,246 | 23,258
Total derivative contracts in a payable position | 4 | 4
Total liabilities | 4 | 4
Fair value, measurements, recurring | Credit contracts |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total derivative contracts in a payable position | 4 | 4
Fair value, measurements, recurring | Equity securities |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Equity securities | 892 | 820
Carrying amount, equity investments without a readily determinable fair value | 50 | 51
Fair value, measurements, recurring | U.S. Treasury and federal agencies |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total available-for-sale securities | 2,086 | 1,873
Fair value, measurements, recurring | U.S. States and political subdivisions |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total available-for-sale securities | 610 | 617
Fair value, measurements, recurring | Foreign government |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total available-for-sale securities | 199 | 194
Fair value, measurements, recurring | Agency mortgage-backed residential |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total available-for-sale securities | 12,687 | 13,653
Fair value, measurements, recurring | Mortgage-backed residential |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total available-for-sale securities | 205 | 206
Fair value, measurements, recurring | Agency mortgage-backed commercial |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total available-for-sale securities | 4,671 | 3,984
Fair value, measurements, recurring | Asset-backed |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total available-for-sale securities | 74 | 129
Fair value, measurements, recurring | Corporate debt |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total available-for-sale securities | 1,814 | 1,754
Fair value, measurements, recurring | Interest rate contracts |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Derivative contracts in a receivable position | 2 | 3
Fair value, measurements, recurring | Foreign exchange contracts |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Derivative contracts in a receivable position |  | 9
Fair value, measurements, recurring | Level 1 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total available-for-sale securities | 2,120 | 1,909
Mortgage loans held-for-sale | 0 | 0
Derivative contracts in a receivable position | 0 | 0
Total assets | 3,012 | 2,729
Total derivative contracts in a payable position | 0 | 0
Total liabilities | 0 | 0
Fair value, measurements, recurring | Level 1 | Credit contracts |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total derivative contracts in a payable position | 0 | 0
Fair value, measurements, recurring | Level 1 | Equity securities |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Equity securities | 892 | 820
Fair value, measurements, recurring | Level 1 | U.S. Treasury and federal agencies |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total available-for-sale securities | 2,086 | 1,873
Fair value, measurements, recurring | Level 1 | U.S. States and political subdivisions |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total available-for-sale securities | 0 | 0
Fair value, measurements, recurring | Level 1 | Foreign government |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total available-for-sale securities | 34 | 36
Fair value, measurements, recurring | Level 1 | Agency mortgage-backed residential |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total available-for-sale securities | 0 | 0
Fair value, measurements, recurring | Level 1 | Mortgage-backed residential |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total available-for-sale securities | 0 | 0
Fair value, measurements, recurring | Level 1 | Agency mortgage-backed commercial |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total available-for-sale securities | 0 | 0
Fair value, measurements, recurring | Level 1 | Asset-backed |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total available-for-sale securities | 0 | 0
Fair value, measurements, recurring | Level 1 | Corporate debt |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total available-for-sale securities | 0 | 0
Fair value, measurements, recurring | Level 1 | Interest rate contracts |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Derivative contracts in a receivable position | 0 | 0
Fair value, measurements, recurring | Level 1 | Foreign exchange contracts |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Derivative contracts in a receivable position |  | 0
Fair value, measurements, recurring | Level 2 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total available-for-sale securities | 20,191 | 20,466
Mortgage loans held-for-sale | 3 | 11
Derivative contracts in a receivable position | 2 | 11
Total assets | 20,196 | 20,488
Total derivative contracts in a payable position | 0 | 0
Total liabilities | 0 | 0
Fair value, measurements, recurring | Level 2 | Credit contracts |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total derivative contracts in a payable position | 0 | 0
Fair value, measurements, recurring | Level 2 | Equity securities |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Equity securities | 0 | 0
Fair value, measurements, recurring | Level 2 | U.S. Treasury and federal agencies |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total available-for-sale securities | 0 | 0
Fair value, measurements, recurring | Level 2 | U.S. States and political subdivisions |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total available-for-sale securities | 575 | 582
Fair value, measurements, recurring | Level 2 | Foreign government |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total available-for-sale securities | 165 | 158
Fair value, measurements, recurring | Level 2 | Agency mortgage-backed residential |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total available-for-sale securities | 12,687 | 13,653
Fair value, measurements, recurring | Level 2 | Mortgage-backed residential |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total available-for-sale securities | 205 | 206
Fair value, measurements, recurring | Level 2 | Agency mortgage-backed commercial |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total available-for-sale securities | 4,671 | 3,984
Fair value, measurements, recurring | Level 2 | Asset-backed |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total available-for-sale securities | 74 | 129
Fair value, measurements, recurring | Level 2 | Corporate debt |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total available-for-sale securities | 1,814 | 1,754
Fair value, measurements, recurring | Level 2 | Interest rate contracts |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Derivative contracts in a receivable position | 2 | 2
Fair value, measurements, recurring | Level 2 | Foreign exchange contracts |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Derivative contracts in a receivable position |  | 9
Fair value, measurements, recurring | Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total available-for-sale securities | 35 | 35
Mortgage loans held-for-sale | 3 | 5
Derivative contracts in a receivable position | 0 | 1
Total assets | 38 | 41
Total derivative contracts in a payable position | 4 | 4
Total liabilities | 4 | 4
Fair value, measurements, recurring | Level 3 | Credit contracts |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total derivative contracts in a payable position | 4 | 4
Fair value, measurements, recurring | Level 3 | Equity securities |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Equity securities | 0 | 0
Fair value, measurements, recurring | Level 3 | U.S. Treasury and federal agencies |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total available-for-sale securities | 0 | 0
Fair value, measurements, recurring | Level 3 | U.S. States and political subdivisions |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total available-for-sale securities | 35 | 35
Fair value, measurements, recurring | Level 3 | Foreign government |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total available-for-sale securities | 0 | 0
Fair value, measurements, recurring | Level 3 | Agency mortgage-backed residential |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total available-for-sale securities | 0 | 0
Fair value, measurements, recurring | Level 3 | Mortgage-backed residential |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total available-for-sale securities | 0 | 0
Fair value, measurements, recurring | Level 3 | Agency mortgage-backed commercial |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total available-for-sale securities | 0 | 0
Fair value, measurements, recurring | Level 3 | Asset-backed |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total available-for-sale securities | 0 | 0
Fair value, measurements, recurring | Level 3 | Corporate debt |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total available-for-sale securities | 0 | 0
Fair value, measurements, recurring | Level 3 | Interest rate contracts |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Derivative contracts in a receivable position | $ 0 | 1
Fair value, measurements, recurring | Level 3 | Foreign exchange contracts |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Derivative contracts in a receivable position |  | $ 0

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