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Fair Value Measurement - Fair Value Level 3 Rollforward Recurring Basis (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2023 | Jun. 30, 2022 | Jun. 30, 2023 | Jun. 30, 2022
FG VIEs’ Assets |  |  |  |
Fair Value Level 3 Rollforward |  |  |  |
Fair value at beginning of period | $ 197 | $ 267 | $ 204 | $ 260
Total pre-tax realized and unrealized gains (losses) recorded in: |  |  |  |
Net income (loss) | (2) | 1 | (1) | (3)
Other comprehensive income (loss) | 0 | 0 | 0 | 0
Purchases | 0 | 0 | 0 | 0
Sales | 0 | 0 | 0 | 0
Settlements | (7) | (26) | (15) | (34)
Consolidations |  |  |  | 15
Deconsolidations |  | 15 |  | (15)
Transfers out of Level 3 |  | 4 |  |
Fair value at end of period | 188 | 223 | 188 | 223
Change in unrealized gains/(losses) related to financial instruments held | (3) | 2 | (3) | (2)
Consolidated Investment Vehicles | Equity securities and warrants |  |  |  |
Fair Value Level 3 Rollforward |  |  |  |
Fair value at beginning of period | 329 | 243 | 297 |
Total pre-tax realized and unrealized gains (losses) recorded in: |  |  |  |
Net income (loss) | 7 | 16 | 40 |
Other comprehensive income (loss) | 0 | 0 | 0 |
Purchases | 34 | 5 | 38 |
Sales | (80) | (6) | (85) |
Settlements | 0 | 0 | 0 |
Deconsolidations |  | 0 |  |
Transfers out of Level 3 |  | 0 |  |
Fair value at end of period | 290 | 258 | 290 | 258
Change in unrealized gains/(losses) related to financial instruments held | (33) | 10 | (1) |
Consolidated Investment Vehicles | Equity Securities |  |  |  |
Fair Value Level 3 Rollforward |  |  |  |
Fair value at beginning of period |  |  |  | 239
Total pre-tax realized and unrealized gains (losses) recorded in: |  |  |  |
Net income (loss) |  |  |  | 26
Other comprehensive income (loss) |  |  |  | 0
Purchases |  |  |  | 5
Sales |  |  |  | (12)
Settlements |  |  |  | 0
Consolidations |  |  |  | 0
Deconsolidations |  |  |  | 0
Fair value at end of period |  | 258 |  | 258
Change in unrealized gains/(losses) related to financial instruments held |  |  |  | 18
Consolidated Investment Vehicles | Corporate securities |  |  |  |
Fair Value Level 3 Rollforward |  |  |  |
Fair value at beginning of period | 93 | 83 | 96 | 91
Total pre-tax realized and unrealized gains (losses) recorded in: |  |  |  |
Net income (loss) | (1) | 7 | (3) | 6
Other comprehensive income (loss) | 0 | 0 | 0 | 0
Purchases | 2 | 0 | 6 | 1
Sales | (10) | 0 | (15) | (8)
Settlements | 0 | 0 | 0 | 0
Consolidations |  |  |  | 0
Deconsolidations |  | 0 |  | 0
Transfers out of Level 3 |  | 0 |  |
Fair value at end of period | 84 | 90 | 84 | 90
Change in unrealized gains/(losses) related to financial instruments held | 0 | 7 | (3) | 5
Consolidated Investment Vehicles | Structured products |  |  |  |
Fair Value Level 3 Rollforward |  |  |  |
Fair value at beginning of period | 17 | 0 | 46 | 0
Total pre-tax realized and unrealized gains (losses) recorded in: |  |  |  |
Net income (loss) | 0 | (3) | 2 | (3)
Other comprehensive income (loss) | 0 | 0 | 0 | 0
Purchases | 0 | 42 | 0 | 42
Sales | (17) | (21) | (48) | (21)
Settlements | 0 | 0 | 0 | 0
Consolidations |  |  |  | 0
Deconsolidations |  | (20) |  | 20
Transfers out of Level 3 |  | 0 |  |
Fair value at end of period | 0 | 38 | 0 | 38
Change in unrealized gains/(losses) related to financial instruments held | 0 | (3) | 0 | (3)
Other |  |  |  |
Fair Value Level 3 Rollforward |  |  |  |
Fair value at beginning of period | 34 | 28 | 50 | 27
Total pre-tax realized and unrealized gains (losses) recorded in: |  |  |  |
Net income (loss) | 3 | 10 | (13) | 11
Other comprehensive income (loss) | 0 | (1) | 0 | (1)
Purchases | 0 | 0 | 0 | 0
Sales | 0 | 0 | 0 | 0
Settlements | (4) | 0 | (4) | 0
Consolidations |  |  |  | 0
Deconsolidations |  | 0 |  | 0
Transfers out of Level 3 |  | 0 |  |
Fair value at end of period | 33 | 37 | 33 | 37
Change in unrealized gains/(losses) related to financial instruments held | 3 | 10 | (13) | 11
Other | Other Comprehensive Income (Loss) |  |  |  |
Total pre-tax realized and unrealized gains (losses) recorded in: |  |  |  |
Change in unrealized gains/(losses) related to financial instruments held | 0 | (1) | 0 | (1)
Financial Guaranty Variable Interest Entities |  |  |  |
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Fair value at start of period | (704) | (335) | (715) | (289)
Total Pretax Realized And Unrealized Gains (Losses) Recorded As Liabilities [Abstract] |  |  |  |
Net income (loss) | (2) | 11 | 1 | 26
Other comprehensive income (loss) | 2 | 3 | 1 | 3
Issuances |  | 0 |  | 0
Settlements | 5 | 24 | 14 | 65
Consolidations |  |  |  | (102)
Deconsolidations |  | 15 |  | 15
Fair value at end of period | (699) | (282) | (699) | (282)
Change in unrealized gains/(losses) included in earnings related to financial instruments | 4 | 11 | 2 | 49
Change in unrealized gains/(losses) included in OCI related to financial instruments | 2 | 3 | 1 | 3
Liabilities of CIVs |  |  |  |
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Fair value at start of period | (4,220) | (3,650) | (4,154) | (3,705)
Total Pretax Realized And Unrealized Gains (Losses) Recorded As Liabilities [Abstract] |  |  |  |
Net income (loss) | 17 | 250 | (45) | 295
Other comprehensive income (loss) | (5) | 37 | (13) | 56
Issuances |  | (1,027) |  | (1,408)
Settlements | 9 | 29 | 13 | 401
Consolidations |  |  |  | 0
Deconsolidations |  | 374 |  | 374
Fair value at end of period | (4,199) | (3,987) | (4,199) | (3,987)
Change in unrealized gains/(losses) included in earnings related to financial instruments | (2) | 262 | (67) | 303
Change in unrealized gains/(losses) included in OCI related to financial instruments | (5) | 37 | (13) | 56
Obligations of state and political subdivisions | Fixed-maturity securities, available-for-sale |  |  |  |
Fair Value Level 3 Rollforward |  |  |  |
Fair value at beginning of period | 47 | 70 | 47 | 72
Total pre-tax realized and unrealized gains (losses) recorded in: |  |  |  |
Net income (loss) | 1 | (1) | 1 | 0
Other comprehensive income (loss) | (1) | (3) | 0 | (8)
Purchases | 0 | 0 | 0 | 0
Sales | 0 | 0 | 0 | 0
Settlements | (1) | (14) | (2) | (13)
Consolidations |  |  |  | 0
Deconsolidations |  | 0 |  | 0
Transfers out of Level 3 |  | 1 |  |
Fair value at end of period | 46 | 51 | 46 | 51
Obligations of state and political subdivisions | Fixed-maturity securities, available-for-sale | Other Comprehensive Income (Loss) |  |  |  |
Total pre-tax realized and unrealized gains (losses) recorded in: |  |  |  |
Change in unrealized gains/(losses) related to financial instruments held | (1) | (4) | 0 | (10)
RMBS | Fixed-maturity securities, available-for-sale |  |  |  |
Fair Value Level 3 Rollforward |  |  |  |
Fair value at beginning of period | 174 | 200 | 179 | 216
Total pre-tax realized and unrealized gains (losses) recorded in: |  |  |  |
Net income (loss) | 4 | 6 | 7 | 10
Other comprehensive income (loss) | (7) | (11) | (8) | (19)
Purchases | 0 | 0 | 0 | 0
Sales | 0 | 0 | 0 | 0
Settlements | (9) | (11) | (16) | (23)
Consolidations |  |  |  | 0
Deconsolidations |  | 0 |  | 0
Transfers out of Level 3 |  | 0 |  |
Fair value at end of period | 162 | 184 | 162 | 184
RMBS | Fixed-maturity securities, available-for-sale | Other Comprehensive Income (Loss) |  |  |  |
Total pre-tax realized and unrealized gains (losses) recorded in: |  |  |  |
Change in unrealized gains/(losses) related to financial instruments held | (7) | (10) | (8) | (17)
Asset-backed securities | Fixed-maturity securities, available-for-sale |  |  |  |
Fair Value Level 3 Rollforward |  |  |  |
Fair value at beginning of period | 795 | 842 | 794 | 863
Total pre-tax realized and unrealized gains (losses) recorded in: |  |  |  |
Net income (loss) | (3) | (3) | 0 | 0
Other comprehensive income (loss) | (5) | (30) | (8) | (37)
Purchases | 18 | 10 | 23 | 35
Sales | (2) | (9) | (2) | (12)
Settlements | (3) | (5) | (7) | (44)
Consolidations |  |  |  | 0
Deconsolidations |  | 0 |  | 0
Transfers out of Level 3 |  | 0 |  |
Fair value at end of period | 800 | 805 | 800 | 805
Asset-backed securities | Fixed-maturity securities, available-for-sale | Other Comprehensive Income (Loss) |  |  |  |
Total pre-tax realized and unrealized gains (losses) recorded in: |  |  |  |
Change in unrealized gains/(losses) related to financial instruments held | (4) | (29) | (7) | (36)
Credit Risk Contract |  |  |  |
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward] |  |  |  |
Fair value at start of period | (148) | (156) | (162) | (154)
Total pre-tax realized and unrealized gains (losses) recorded in: |  |  |  |
Net income (loss) | 91 | 9 | 106 | 6
Other comprehensive income (loss) | 0 | 0 | 0 | 0
Issuances |  | 0 |  | 0
Settlements | 0 | 0 | (1) | 1
Consolidations |  |  |  | 0
Deconsolidations |  | 0 |  | 0
Fair value at end of period | (57) | (147) | (57) | (147)
Change in unrealized gains/(losses) included in earnings related to financial instruments | $ 91 | $ 8 | $ 105 | $ 5

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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 unrealized gain (loss) recognized in other comprehensive income (OCI) 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 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 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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