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Fair Value Measurement - Level 3 Recurring Fair Value Rollforward (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
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 | $ 2,232 | $ 2,675 |
Derivative liabilities, gross amount | 2,032 | 2,932 |
Recurring | Level 3 |  |  |
Derivative, Fair Value, Net [Abstract] |  |  |
Beginning balance | 58 |  |
Ending balance | 69 | 58 |
Net unrealized gains (losses) included in OCI related to assets and liabilities still held | (10) | (5) | $ (57)
Derivative assets, gross amount | 683 | 886 | 79
Derivative liabilities, gross amount | 614 | 828 | 74
Total RMBS | Recurring | Level 3 |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Beginning balance | 146 | 236 | 258
Total Gains or (Losses) (Realized/Unrealized), Included in Net Income | 6 | 8 | 18
Total Gains or (Losses) (Realized/Unrealized), Included in OCI | (2) | (2) | (32)
Purchases | 0 | 0 | 0
Sales | 0 | 0 | 0
Issuances | 0 | 0 | 0
Settlements | (11) | (20) | (60)
Transfers Into Level 3 | 193 | 49 | 123
Transfers Out of Level 3 | (216) | (125) | (71)
Ending balance | 116 | 146 | 236
Derivative, Fair Value, Net [Abstract] |  |  |
Net Unrealized Gains (Losses) Included in Net Income Related to Assets and Liabilities Still Held | 6 | 7 | 10
CMBS | Recurring | Level 3 |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Beginning balance | 132 | 142 | 9
Total Gains or (Losses) (Realized/Unrealized), Included in Net Income | 0 | (1) | (1)
Total Gains or (Losses) (Realized/Unrealized), Included in OCI | (3) | (4) | (3)
Purchases | 0 | 0 | 0
Sales | 0 | 0 | 0
Issuances | 0 | 0 | 0
Settlements | (3) | (5) | (15)
Transfers Into Level 3 | 0 | 0 | 190
Transfers Out of Level 3 | (124) | 0 | (38)
Ending balance | 2 | 132 | 142
Derivative, Fair Value, Net [Abstract] |  |  |
Net Unrealized Gains (Losses) Included in Net Income Related to Assets and Liabilities Still Held | 0 | (1) | (1)
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 | 267
Total Gains or (Losses) (Realized/Unrealized), Included in Net Income | 6 | 7 | 17
Total Gains or (Losses) (Realized/Unrealized), Included in OCI | (5) | (6) | (35)
Purchases | 0 | 0 | 0
Sales | 0 | 0 | 0
Issuances | 0 | 0 | 0
Settlements | (14) | (25) | (75)
Transfers Into Level 3 | 193 | 49 | 313
Transfers Out of Level 3 | (340) | (125) | (109)
Ending balance | 118 | 278 | 378
Derivative, Fair Value, Net [Abstract] |  |  |
Net Unrealized Gains (Losses) Included in Net Income Related to Assets and Liabilities Still Held | 6 | 6 | 9
Retained interests in securitizations | Recurring | Level 3 |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Beginning balance | 35 | 36 | 41
Total Gains or (Losses) (Realized/Unrealized), Included in Net Income | (1) | (1) | (5)
Total Gains or (Losses) (Realized/Unrealized), Included in OCI | 0 | 0 | 0
Purchases | 0 | 0 | 0
Sales | 0 | 0 | 0
Issuances | 0 | 0 | 0
Settlements | 0 | 0 | 0
Transfers Into Level 3 | 0 | 0 | 0
Transfers Out of Level 3 | 0 | 0 | 0
Ending balance | 34 | 35 | 36
Derivative, Fair Value, Net [Abstract] |  |  |
Net Unrealized Gains (Losses) Included in Net Income Related to Assets and Liabilities Still Held | (1) | (1) | (5)
Net derivative assets (liabilities) | Recurring | Level 3 |  |  |
Derivative, Fair Value, Net [Abstract] |  |  |
Beginning balance | 58 | 5 | 19
Total Gains or (Losses) (Realized/Unrealized), Included in Net Income | (15) | (14) | (65)
Total Gains or (Losses) (Realized/Unrealized), Included in OCI | 0 | 0 | 0
Purchases | 0 | 0 | 0
Sales | 0 | 0 | 0
Issuances | 12 | 166 | 36
Settlements | 16 | 69 | 3
Transfers Into Level 3 | (2) | (167) | (28)
Transfers Out of Level 3 | 0 | (1) | 40
Ending balance | 69 | 58 | 5
Net Unrealized Gains (Losses) Included in Net Income Related to Assets and Liabilities Still Held | $ (25) | $ 63 | $ (33)

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- Definition Amount of unrealized gain (loss) which is included in other comprehensive income related to those assets still held at the reporting date for which fair value is measured on a recurring basis using significant unobservable inputs (Level 3) + References No definition available. + Details
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- Definition Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and elected not to be offset. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 320 -Name Accounting Standards Codification -Section S99 -Paragraph 5C -Subparagraph (SX 210.12-13C(Column F)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477271/946-320-S99-5C Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 320 -Name Accounting Standards Codification -Section S99 -Paragraph 5B -Subparagraph (SX 210.12-13B(Column E)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477271/946-320-S99-5B Reference 3: http://www.xbrl.org/2003/role/exampleRef -Topic 210 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 22 -Publisher FASB -URI https://asc.fasb.org/1943274/2147483444/210-20-55-22 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 210 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147483466/210-20-50-3 + Details
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- Definition Amount of unrealized gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3) and still held. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 101 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482078/820-10-55-101 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-3 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 102 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482078/820-10-55-102 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 + Details
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- Definition Amount of gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3). + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 101 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482078/820-10-55-101 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-3 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 102 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482078/820-10-55-102 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (c)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 + Details
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- Definition Amount of gain (loss) recognized in other comprehensive income (OCI) from asset measured at fair value on recurring basis using unobservable input (level 3). + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 101 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482078/820-10-55-101 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-3 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (c)(1a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 + Details
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