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Variable Interest Entities and Securitizations - Carrying Amount of Consolidated and Unconsolidated VIEs (Details) - USD ($) $ in Millions | Sep. 30, 2024 | Dec. 31, 2023
--- | --- | ---
Variable Interest Entity [Line Items] |  |
Carrying Amount of Assets | $ 486,433 | $ 478,464
Carrying Amount of Liabilities | 423,508 | 420,375
Maximum Exposure to Loss | 5,854 | 6,175
Consolidated |  |
Variable Interest Entity [Line Items] |  |
Carrying Amount of Assets | 30,466 | 33,288
Carrying Amount of Liabilities | 16,368 | 18,746
Unconsolidated |  |
Variable Interest Entity [Line Items] |  |
Carrying Amount of Assets | 5,854 | 6,175
Carrying Amount of Liabilities | 1,898 | 2,085
Affordable housing entities |  |
Variable Interest Entity [Line Items] |  |
Maximum Exposure to Loss | 5,469 | 5,726
VIE, nonconsolidated, carrying amount of assets included in certain investment structures | 2,600 | 2,600
VIE, nonconsolidated, carrying amount of liabilities included in certain investment structures | 999 | 989
Affordable housing entities | Consolidated |  |
Variable Interest Entity [Line Items] |  |
Carrying Amount of Assets | 354 | 297
Carrying Amount of Liabilities | 75 | 23
Affordable housing entities | Unconsolidated |  |
Variable Interest Entity [Line Items] |  |
Carrying Amount of Assets | 5,469 | 5,726
Carrying Amount of Liabilities | 1,890 | 2,085
Entities that provide capital to low-income and rural communities |  |
Variable Interest Entity [Line Items] |  |
Maximum Exposure to Loss | 0 | 0
Entities that provide capital to low-income and rural communities | Consolidated |  |
Variable Interest Entity [Line Items] |  |
Carrying Amount of Assets | 2,639 | 2,498
Carrying Amount of Liabilities | 10 | 10
Entities that provide capital to low-income and rural communities | Unconsolidated |  |
Variable Interest Entity [Line Items] |  |
Carrying Amount of Assets | 0 | 0
Carrying Amount of Liabilities | 0 | 0
Other |  |
Variable Interest Entity [Line Items] |  |
Maximum Exposure to Loss | 385 | 449
Other | Consolidated |  |
Variable Interest Entity [Line Items] |  |
Carrying Amount of Assets | 0 | 0
Carrying Amount of Liabilities | 0 | 0
Other | Unconsolidated |  |
Variable Interest Entity [Line Items] |  |
Carrying Amount of Assets | 385 | 449
Carrying Amount of Liabilities | 8 | 0
Total other VIEs |  |
Variable Interest Entity [Line Items] |  |
Maximum Exposure to Loss | 5,854 | 6,175
Total other VIEs | Consolidated |  |
Variable Interest Entity [Line Items] |  |
Carrying Amount of Assets | 2,993 | 2,795
Carrying Amount of Liabilities | 85 | 33
Total other VIEs | Unconsolidated |  |
Variable Interest Entity [Line Items] |  |
Carrying Amount of Assets | 5,854 | 6,175
Carrying Amount of Liabilities | 1,898 | 2,085
Credit card loan securitizations |  |
Variable Interest Entity [Line Items] |  |
Maximum Exposure to Loss | 0 | 0
Credit card loan securitizations | Consolidated |  |
Variable Interest Entity [Line Items] |  |
Carrying Amount of Assets | 24,000 | 25,474
Carrying Amount of Liabilities | 13,495 | 14,692
Credit card loan securitizations | Unconsolidated |  |
Variable Interest Entity [Line Items] |  |
Carrying Amount of Assets | 0 | 0
Carrying Amount of Liabilities | 0 | 0
Auto loan securitizations |  |
Variable Interest Entity [Line Items] |  |
Maximum Exposure to Loss | 0 | 0
Auto loan securitizations | Consolidated |  |
Variable Interest Entity [Line Items] |  |
Carrying Amount of Assets | 3,473 | 5,019
Carrying Amount of Liabilities | 2,788 | 4,021
Auto loan securitizations | Unconsolidated |  |
Variable Interest Entity [Line Items] |  |
Carrying Amount of Assets | 0 | 0
Carrying Amount of Liabilities | 0 | 0
Total securitization-related VIEs |  |
Variable Interest Entity [Line Items] |  |
Maximum Exposure to Loss | 0 | 0
Total securitization-related VIEs | Consolidated |  |
Variable Interest Entity [Line Items] |  |
Carrying Amount of Assets | 27,473 | 30,493
Carrying Amount of Liabilities | 16,283 | 18,713
Total securitization-related VIEs | Unconsolidated |  |
Variable Interest Entity [Line Items] |  |
Carrying Amount of Assets | 0 | 0
Carrying Amount of Liabilities | $ 0 | $ 0

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