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Fair Value Measurement - Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Millions | 9 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Sep. 30, 2024 | Dec. 31, 2023 | Sep. 30, 2023
Assets: |  |  |
Fair Value | $ 83,500 | $ 79,117 |
Loans held for sale | $ 77 | $ 347 |
Derivative Asset, Statement of Financial Position [Extensible Enumeration] | Other assets | Other assets |
Other assets: |  |  |
Derivative assets, gross amount | $ 2,408 | $ 2,675 |
Derivative Asset, netting adjustments | (725) | (1,005) |
Derivative asset | 1,683 | 1,670 |
Liabilities: |  |  |
Derivative liabilities, gross amount | 2,657 | 2,932 |
Derivative Liability, netting adjustments | (622) | (597) |
Derivative liability | $ 2,035 | $ 2,335 |
Derivative Liability, Statement of Financial Position [Extensible Enumeration] | Other liabilities | Other liabilities |
Net valuation allowance | $ 3 | $ 2 |
Level 1 |  |  |
Assets: |  |  |
Loans held for sale | 0 | 0 |
Level 2 |  |  |
Assets: |  |  |
Loans held for sale | 19 | 515 |
Level 3 |  |  |
Assets: |  |  |
Loans held for sale | 0 | 0 |
Recurring |  |  |
Assets: |  |  |
Fair Value | 83,500 | 79,117 |
Loans held for sale | 77 | 347 |
Other assets: |  |  |
Derivative asset | 1,683 | 1,670 |
Other | 709 | 627 |
Total | 85,969 | 81,761 |
Liabilities: |  |  |
Derivative liability | 2,035 | 2,335 |
Recurring | Level 1 |  |  |
Assets: |  |  |
Fair Value | 6,163 | 5,408 |
Loans held for sale | 0 | 0 |
Other assets: |  |  |
Derivative assets, gross amount | 866 | 788 |
Other | 675 | 589 |
Total | 7,704 | 6,785 |
Liabilities: |  |  |
Derivative liabilities, gross amount | 574 | 449 |
Deferred compensation plan assets | 670 | 578 |
Recurring | Level 2 |  |  |
Assets: |  |  |
Fair Value | 77,155 | 73,431 |
Loans held for sale | 77 | 347 |
Other assets: |  |  |
Derivative assets, gross amount | 929 | 1,001 |
Other | 0 | 3 |
Total | 78,161 | 74,782 |
Liabilities: |  |  |
Derivative liabilities, gross amount | 1,515 | 1,655 |
Recurring | Level 3 |  |  |
Assets: |  |  |
Fair Value | 182 | 278 |
Loans held for sale | 0 | 0 |
Other assets: |  |  |
Derivative assets, gross amount | 613 | 886 | $ 1,300
Other | 34 | 35 |
Total | 829 | 1,199 |
Liabilities: |  |  |
Derivative liabilities, gross amount | 568 | 828 | $ 1,300
Retained interests in securitizations | 34 | 35 |
Recurring | Fair Value Inputs Level 1 And Level 2 |  |  |
Liabilities: |  |  |
Equity securities | 5 | 14 |
Debt and equity securities, unrealized gain (loss) | 5 | 5 |
U.S. Treasury securities |  |  |
Assets: |  |  |
Fair Value | 6,032 | 5,282 |
U.S. Treasury securities | Recurring |  |  |
Assets: |  |  |
Fair Value | 6,032 | 5,282 |
U.S. Treasury securities | Recurring | Level 1 |  |  |
Assets: |  |  |
Fair Value | 6,032 | 5,282 |
U.S. Treasury securities | Recurring | Level 2 |  |  |
Assets: |  |  |
Fair Value | 0 | 0 |
U.S. Treasury securities | Recurring | Level 3 |  |  |
Assets: |  |  |
Fair Value | 0 | 0 |
Total RMBS |  |  |
Assets: |  |  |
Fair Value | 66,307 | 63,638 |
Total RMBS | Recurring |  |  |
Assets: |  |  |
Fair Value | 66,307 | 63,638 |
Total RMBS | Recurring | Level 1 |  |  |
Assets: |  |  |
Fair Value | 0 | 0 |
Total RMBS | Recurring | Level 2 |  |  |
Assets: |  |  |
Fair Value | 66,127 | 63,492 |
Total RMBS | Recurring | Level 3 |  |  |
Assets: |  |  |
Fair Value | 180 | 146 |
CMBS | Recurring |  |  |
Assets: |  |  |
Fair Value | 8,183 | 8,323 |
CMBS | Recurring | Level 1 |  |  |
Assets: |  |  |
Fair Value | 0 | 0 |
CMBS | Recurring | Level 2 |  |  |
Assets: |  |  |
Fair Value | 8,181 | 8,191 |
CMBS | Recurring | Level 3 |  |  |
Assets: |  |  |
Fair Value | 2 | 132 |
Other securities |  |  |
Assets: |  |  |
Fair Value | 2,978 | 1,874 |
Other securities | Recurring |  |  |
Assets: |  |  |
Fair Value | 2,978 | 1,874 |
Other securities | Recurring | Level 1 |  |  |
Assets: |  |  |
Fair Value | 131 | 126 |
Other securities | Recurring | Level 2 |  |  |
Assets: |  |  |
Fair Value | 2,847 | 1,748 |
Other securities | Recurring | Level 3 |  |  |
Assets: |  |  |
Fair Value | $ 0 | $ 0 |

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