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Fair Value Measurement - Level 3 Recurring Fair Value Rollforward (Details) - USD ($) $ in Millions | 3 Months Ended |
--- | --- | ---
Mar. 31, 2024 | Mar. 31, 2023 | Dec. 31, 2023
Derivative, Fair Value, Net [Abstract] |  |  |
Fair Value, Net Derivative Asset (Liability), Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] | Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent |  |
Derivative assets, gross amount | $ 2,649 |  | $ 2,675
Derivative liabilities, gross amount | 2,934 |  | 2,932
Recurring | Level 3 |  |  |
Derivative, Fair Value, Net [Abstract] |  |  |
Beginning balance | 58 |  |
Ending balance | 54 |  |
Net unrealized gains (losses) included in OCI related to assets and liabilities still held | (8) | $ (8) |
Derivative assets, gross amount | 974 | 837 | 886
Derivative liabilities, gross amount | 920 | 819 | $ 828
Total RMBS | Recurring | Level 3 |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Beginning balance | 146 | 236 |
Total Gains or (Losses) (Realized/Unrealized), Included in Net Income | 2 | 1 |
Total Gains or (Losses) (Realized/Unrealized), Included in OCI | 0 | 3 |
Purchases | 0 | 0 |
Sales | 0 | 0 |
Issuances | 0 | 0 |
Settlements | (3) | (5) |
Transfers Into Level 3 | 182 | 34 |
Transfers Out of Level 3 | (18) | (22) |
Ending balance | 309 | 247 |
Derivative, Fair Value, Net [Abstract] |  |  |
Net Unrealized Gains (Losses) Included in Net Income Related to Assets and Liabilities Still Held | 2 | 2 |
CMBS | Recurring | Level 3 |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Beginning balance | 132 | 142 |
Total Gains or (Losses) (Realized/Unrealized), Included in Net Income | 0 | 0 |
Total Gains or (Losses) (Realized/Unrealized), Included in OCI | (2) | 5 |
Purchases | 0 | 0 |
Sales | 0 | 0 |
Issuances | 0 | 0 |
Settlements | (1) | (2) |
Transfers Into Level 3 | 0 | 0 |
Transfers Out of Level 3 | 0 | 0 |
Ending balance | 129 | 145 |
Derivative, Fair Value, Net [Abstract] |  |  |
Net Unrealized Gains (Losses) Included in Net Income Related to Assets and Liabilities Still Held | 0 | 0 |
Total securities available for sale | Recurring | Level 3 |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Beginning balance | 278 | 378 |
Total Gains or (Losses) (Realized/Unrealized), Included in Net Income | 2 | 1 |
Total Gains or (Losses) (Realized/Unrealized), Included in OCI | (2) | 8 |
Purchases | 0 | 0 |
Sales | 0 | 0 |
Issuances | 0 | 0 |
Settlements | (4) | (7) |
Transfers Into Level 3 | 182 | 34 |
Transfers Out of Level 3 | (18) | (22) |
Ending balance | 438 | 392 |
Derivative, Fair Value, Net [Abstract] |  |  |
Net Unrealized Gains (Losses) Included in Net Income Related to Assets and Liabilities Still Held | 2 | 2 |
Retained interests in securitizations | Recurring | Level 3 |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Beginning balance | 35 | 36 |
Total Gains or (Losses) (Realized/Unrealized), Included in Net Income | 0 | 0 |
Total Gains or (Losses) (Realized/Unrealized), Included in OCI | 0 | 0 |
Purchases | 0 | 0 |
Sales | 0 | 0 |
Issuances | 0 | 0 |
Settlements | 0 | 0 |
Transfers Into Level 3 | 0 | 0 |
Transfers Out of Level 3 | 0 | 0 |
Ending balance | 35 | 36 |
Derivative, Fair Value, Net [Abstract] |  |  |
Net Unrealized Gains (Losses) Included in Net Income Related to Assets and Liabilities Still Held | 0 | 0 |
Net derivative assets (liabilities) | Recurring | Level 3 |  |  |
Derivative, Fair Value, Net [Abstract] |  |  |
Beginning balance | 58 | 5 |
Total Gains or (Losses) (Realized/Unrealized), Included in Net Income | 6 | (5) |
Total Gains or (Losses) (Realized/Unrealized), Included in OCI | 0 | 0 |
Purchases | 0 | 0 |
Sales | 0 | 0 |
Issuances | (5) | 104 |
Settlements | (5) | 12 |
Transfers Into Level 3 | 0 | (97) |
Transfers Out of Level 3 | 0 | (1) |
Ending balance | 54 | 18 |
Net Unrealized Gains (Losses) Included in Net Income Related to Assets and Liabilities Still Held | $ (1) | $ 4 |

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Data Type: | na
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