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Fair Value Measurement - Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Mar. 31, 2024 | Dec. 31, 2023 | Mar. 31, 2023
Assets: |  |  |
Fair Value | $ 78,398 | $ 79,117 |
Loans held for sale | $ 1,200 | $ 347 |
Derivative Asset, Statement of Financial Position [Extensible Enumeration] | Other assets | Other assets |
Other assets: |  |  |
Derivative assets, gross amount | $ 2,649 | $ 2,675 |
Derivative Asset, netting adjustments | (1,050) | (1,005) |
Derivative asset | 1,599 | 1,670 |
Liabilities: |  |  |
Derivative liabilities, gross amount | 2,934 | 2,932 |
Derivative Liability, netting adjustments | (440) | (597) |
Derivative liability | $ 2,494 | $ 2,335 |
Derivative Liability, Statement of Financial Position [Extensible Enumeration] | Other liabilities | Other liabilities |
Net valuation allowance | $ 1 | $ 2 |
Level 1 |  |  |
Assets: |  |  |
Loans held for sale | 0 | 0 |
Level 2 |  |  |
Assets: |  |  |
Loans held for sale | 431 | 515 |
Level 3 |  |  |
Assets: |  |  |
Loans held for sale | 0 | 0 |
Recurring |  |  |
Assets: |  |  |
Fair Value | 78,398 | 79,117 |
Loans held for sale | 1,212 | 347 |
Other assets: |  |  |
Derivative asset | 1,599 | 1,670 |
Other | 687 | 627 |
Total | 81,896 | 81,761 |
Liabilities: |  |  |
Derivative liability | 2,494 | 2,335 |
Recurring | Level 1 |  |  |
Assets: |  |  |
Fair Value | 5,898 | 5,408 |
Loans held for sale | 0 | 0 |
Other assets: |  |  |
Derivative assets, gross amount | 733 | 788 |
Other | 649 | 589 |
Total | 7,280 | 6,785 |
Liabilities: |  |  |
Derivative liabilities, gross amount | 593 | 449 |
Deferred compensation plan assets | 646 | 578 |
Recurring | Level 2 |  |  |
Assets: |  |  |
Fair Value | 72,062 | 73,431 |
Loans held for sale | 1,212 | 347 |
Other assets: |  |  |
Derivative assets, gross amount | 942 | 1,001 |
Other | 3 | 3 |
Total | 74,219 | 74,782 |
Liabilities: |  |  |
Derivative liabilities, gross amount | 1,421 | 1,655 |
Recurring | Level 3 |  |  |
Assets: |  |  |
Fair Value | 438 | 278 |
Loans held for sale | 0 | 0 |
Other assets: |  |  |
Derivative assets, gross amount | 974 | 886 | $ 837
Other | 35 | 35 |
Total | 1,447 | 1,199 |
Liabilities: |  |  |
Derivative liabilities, gross amount | 920 | 828 | $ 819
Retained interests in securitizations | 35 | 35 |
Recurring | Fair Value Inputs Level 1 And Level 2 |  |  |
Liabilities: |  |  |
Equity securities | 6 | 14 |
Debt and equity securities, unrealized gain (loss) | 1 | 5 |
U.S. Treasury securities |  |  |
Assets: |  |  |
Fair Value | 5,728 | 5,282 |
U.S. Treasury securities | Recurring |  |  |
Assets: |  |  |
Fair Value | 5,728 | 5,282 |
U.S. Treasury securities | Recurring | Level 1 |  |  |
Assets: |  |  |
Fair Value | 5,728 | 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 | 62,398 | 63,638 |
Total RMBS | Recurring |  |  |
Assets: |  |  |
Fair Value | 62,398 | 63,638 |
Total RMBS | Recurring | Level 1 |  |  |
Assets: |  |  |
Fair Value | 0 | 0 |
Total RMBS | Recurring | Level 2 |  |  |
Assets: |  |  |
Fair Value | 62,089 | 63,492 |
Total RMBS | Recurring | Level 3 |  |  |
Assets: |  |  |
Fair Value | 309 | 146 |
CMBS | Recurring |  |  |
Assets: |  |  |
Fair Value | 8,193 | 8,323 |
CMBS | Recurring | Level 1 |  |  |
Assets: |  |  |
Fair Value | 0 | 0 |
CMBS | Recurring | Level 2 |  |  |
Assets: |  |  |
Fair Value | 8,064 | 8,191 |
CMBS | Recurring | Level 3 |  |  |
Assets: |  |  |
Fair Value | 129 | 132 |
Other securities |  |  |
Assets: |  |  |
Fair Value | 2,079 | 1,874 |
Other securities | Recurring |  |  |
Assets: |  |  |
Fair Value | 2,079 | 1,874 |
Other securities | Recurring | Level 1 |  |  |
Assets: |  |  |
Fair Value | 170 | 126 |
Other securities | Recurring | Level 2 |  |  |
Assets: |  |  |
Fair Value | 1,909 | 1,748 |
Other securities | Recurring | Level 3 |  |  |
Assets: |  |  |
Fair Value | $ 0 | $ 0 |

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