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Fair Value Measurement - Fair Value Level 3 Rollforward Recurring Basis (Details) - USD ($) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Financial Guaranty Variable Interest Entities |  |  |
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value at start of period | $ (554) | $ (715) | $ (289)
Total pretax realized and unrealized gains/(losses) recorded in: |  |  |
Net income (loss) | 2 | 34 |
Other comprehensive income (loss) | 3 | (3) |
Issuances | 0 | 0 |
Sales |  | 0 |
Settlements | 149 | 99 |
VIE consolidations |  | (571) |
Deconsolidations | 7 | 15 |
Fair value at end of period | 554 | 715 |
Change in unrealized gains/(losses) related to financial instruments held | 0 | 59 |
Financial Guaranty Variable Interest Entities | Other Comprehensive Income (Loss) |  |  |
Total pretax realized and unrealized gains/(losses) recorded in: |  |  |
Change in unrealized gains/(losses) related to financial instruments held | 3 | (3) |
Consolidated Investment Vehicles |  |  |
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |
Fair value at start of period | 0 | (4,154) | $ (3,705)
Total pretax realized and unrealized gains/(losses) recorded in: |  |  |
Net income (loss) | (45) | 178 |
Other comprehensive income (loss) | (13) | 42 |
Issuances | 0 | (1,421) |
Sales |  | 2 |
Settlements | 13 | 402 |
VIE consolidations |  | (26) |
Deconsolidations | 4,199 | 374 |
Fair value at end of period | 0 | 4,154 |
Change in unrealized gains/(losses) related to financial instruments held | 0 | 217 |
Consolidated Investment Vehicles | Other Comprehensive Income (Loss) |  |  |
Total pretax realized and unrealized gains/(losses) recorded in: |  |  |
Change in unrealized gains/(losses) related to financial instruments held | 0 | 42 |
Credit Risk Contract |  |  |
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward] |  |  |
Fair value at beginning of period | (162) | (154) |
Total pre-tax realized and unrealized gains (losses) recorded in: |  |  |
Net income (loss) | 114 | (11) |
Other comprehensive income (loss) | 0 | 0 |
Issuances | (1) | 0 |
Sales |  | 0 |
Settlements | (1) | (3) |
Consolidations |  | 0 |
Deconsolidations | 0 | 0 |
Fair value at end of period | (50) | (162) |
Change in unrealized gains/(losses)included in earnings related to financial instruments | 112 | (11) |
Fixed-maturity securities | Obligations of state and political subdivisions |  |  |
Fair Value Level 3 Rollforward |  |  |
Fair value at beginning of period | 47 | 72 |
Total pretax realized and unrealized gains/(losses) recorded in: |  |  |
Net income (loss) | 1 | 1 |
Other comprehensive income (loss) | (2) | (12) |
Purchases | 0 | 0 |
Sales | 0 | 0 |
Settlements | (3) | (14) |
Consolidation |  | 0 |
Deconsolidations | 0 | 0 |
Transfers into Level 3 | 3 |  |
Transfers out of Level 3 | (40) |  |
Fair value at end of period | 6 | 47 |
Fixed-maturity securities | Obligations of state and political subdivisions | Other Comprehensive Income (Loss) |  |  |
Total pretax realized and unrealized gains/(losses) recorded in: |  |  |
Change in unrealized gains/(losses) related to financial instruments held, Included in OCI | 0 | (12) |
Fixed-maturity securities | RMBS |  |  |
Fair Value Level 3 Rollforward |  |  |
Fair value at beginning of period | 179 | 216 |
Total pretax realized and unrealized gains/(losses) recorded in: |  |  |
Net income (loss) | 13 | 16 |
Other comprehensive income (loss) | (8) | (36) |
Purchases | 0 | 22 |
Sales | 0 | 0 |
Settlements | (30) | (39) |
Consolidation |  | 0 |
Deconsolidations | 0 | 0 |
Transfers into Level 3 | 0 |  |
Transfers out of Level 3 | 0 |  |
Fair value at end of period | 154 | 179 |
Fixed-maturity securities | RMBS | Other Comprehensive Income (Loss) |  |  |
Total pretax realized and unrealized gains/(losses) recorded in: |  |  |
Change in unrealized gains/(losses) related to financial instruments held, Included in OCI | (7) | (32) |
Fixed-maturity securities | Asset-backed securities |  |  |
Fair Value Level 3 Rollforward |  |  |
Fair value at beginning of period | 794 | 863 |
Total pretax realized and unrealized gains/(losses) recorded in: |  |  |
Net income (loss) | 32 | 5 |
Other comprehensive income (loss) | (8) | (47) |
Purchases | 23 | 43 |
Sales | (2) | (13) |
Settlements | (36) | (57) |
Consolidation |  | 0 |
Deconsolidations | 0 | 0 |
Transfers into Level 3 | 0 |  |
Transfers out of Level 3 | 0 |  |
Fair value at end of period | 803 | 794 |
Fixed-maturity securities | Asset-backed securities | Other Comprehensive Income (Loss) |  |  |
Total pretax realized and unrealized gains/(losses) recorded in: |  |  |
Change in unrealized gains/(losses) related to financial instruments held, Included in OCI | 9 | (45) |
Financial Guaranty Variable Interest Entities |  |  |
Fair Value Level 3 Rollforward |  |  |
Fair value at beginning of period | 204 | 260 |
Total pretax realized and unrealized gains/(losses) recorded in: |  |  |
Net income (loss) | 9 | (3) |
Other comprehensive income (loss) | 0 | 0 |
Purchases | 0 | 0 |
Sales | 0 | 0 |
Settlements | (33) | (60) |
Consolidation |  | 22 |
Deconsolidations | (7) | (15) |
Transfers into Level 3 | 1 |  |
Transfers out of Level 3 | 0 |  |
Fair value at end of period | 174 | 204 |
Change in unrealized gains/(losses) related to financial instruments held, Included in OCI | 4 | (3) |
Consolidated Investment Vehicles | Equity securities and warrants |  |  |
Fair Value Level 3 Rollforward |  |  |
Fair value at beginning of period | 297 | 239 |
Total pretax realized and unrealized gains/(losses) recorded in: |  |  |
Net income (loss) | 51 | 1 |
Other comprehensive income (loss) | 0 | 0 |
Purchases | 42 | 73 |
Sales | (91) | (16) |
Settlements | 0 | 0 |
Consolidation |  | 0 |
Deconsolidations | (219) | 0 |
Transfers into Level 3 | 0 |  |
Transfers out of Level 3 | 0 |  |
Fair value at end of period | 80 | 297 |
Change in unrealized gains/(losses) related to financial instruments held, Included in OCI | 11 | (8) |
Consolidated Investment Vehicles | Corporate securities |  |  |
Fair Value Level 3 Rollforward |  |  |
Fair value at beginning of period | 96 | 91 |
Total pretax realized and unrealized gains/(losses) recorded in: |  |  |
Net income (loss) | (3) | 2 |
Other comprehensive income (loss) | 0 | 0 |
Purchases | 6 | 16 |
Sales | (15) | (13) |
Settlements | 0 | 0 |
Consolidation |  | 0 |
Deconsolidations | (84) | 0 |
Transfers into Level 3 | 0 |  |
Transfers out of Level 3 | 0 |  |
Fair value at end of period | 0 | 96 |
Change in unrealized gains/(losses) related to financial instruments held, Included in OCI | 0 | 1 |
Consolidated Investment Vehicles | Structured products |  |  |
Fair Value Level 3 Rollforward |  |  |
Fair value at beginning of period | 46 | 0 |
Total pretax realized and unrealized gains/(losses) recorded in: |  |  |
Net income (loss) | 21 | (5) |
Other comprehensive income (loss) | 0 | 0 |
Purchases | 5 | 52 |
Sales | (48) | (21) |
Settlements | 0 | 0 |
Consolidation |  | 0 |
Deconsolidations | 165 | 20 |
Transfers into Level 3 | 0 |  |
Transfers out of Level 3 | 0 |  |
Fair value at end of period | 189 | 46 |
Change in unrealized gains/(losses) related to financial instruments held, Included in OCI | 10 | (4) |
Other |  |  |
Fair Value Level 3 Rollforward |  |  |
Fair value at beginning of period | 50 | 27 |
Total pretax realized and unrealized gains/(losses) recorded in: |  |  |
Net income (loss) | (32) | 24 |
Other comprehensive income (loss) | 0 | (1) |
Purchases | 0 | 0 |
Sales | 0 | 0 |
Settlements | (4) | 0 |
Consolidation |  | 0 |
Deconsolidations | 0 | 0 |
Transfers into Level 3 | 0 |  |
Transfers out of Level 3 | 0 |  |
Fair value at end of period | 14 | 50 |
Change in unrealized gains/(losses) related to financial instruments held, Included in OCI | (32) | 24 |
Other | Other Comprehensive Income (Loss) |  |  |
Total pretax realized and unrealized gains/(losses) recorded in: |  |  |
Change in unrealized gains/(losses) related to financial instruments held, Included in OCI | $ 0 | $ (1) |

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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/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 unrealized gain (loss) recognized in income from liability measured at fair value on recurring basis using unobservable input (level 3) and still held. + References Reference 1: 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/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/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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- Definition Amount of transfer of financial instrument classified as an asset into level 3 of the fair value hierarchy. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (c)(3) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482106/820-10-50-2 + Details
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- Definition Amount of transfers of financial instrument classified as an asset out of level 3 of the fair value hierarchy. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (c)(3) -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 liability measured at fair value on recurring basis using unobservable input (level 3). + References Reference 1: 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 liability measured at fair value on recurring basis using unobservable input (level 3). + References Reference 1: 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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- Definition Amount of unrealized gain (loss) recognized in income for derivative asset (liability) after deduction of derivative liability (asset), measured at fair value using unobservable input (level 3) and still held. + References Reference 1: 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 derivative asset (liability) after deduction of derivative liability (asset), measured at fair value on recurring basis using unobservable input (level 3). + References Reference 1: 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 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 + Details
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