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Fair Value Measurement - Fair Value Level 3 Rollforward Recurring Basis (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2023 | Sep. 30, 2022 | Sep. 30, 2023 | Sep. 30, 2022
FG VIEs’ Assets |  |  |  |
Fair Value Level 3 Rollforward |  |  |  |
Fair value at beginning of period | $ 188 | $ 223 | $ 204 | $ 260
Total pre-tax realized and unrealized gains (losses) recorded in: |  |  |  |
Net income (loss) | 1 | 3 | 0 | 0
Other comprehensive income (loss) | 0 | 0 | 0 | 0
Purchases | 0 | 0 | 0 | 0
Sales | 0 | 0 | 0 | 0
Settlements | (9) | (16) | (24) | (50)
Consolidations | 0 |  |  | 15
Deconsolidations | 0 |  | 0 | (15)
Transfers out of Level 3 | 0 |  | 0 |
Fair value at end of period | 180 | 210 | 180 | 210
Change in unrealized gains/(losses) related to financial instruments held | 0 | 3 | (3) | 1
Consolidated Investment Vehicles | Equity securities and warrants |  |  |  |
Fair Value Level 3 Rollforward |  |  |  |
Fair value at beginning of period | 290 | 258 | 297 |
Total pre-tax realized and unrealized gains (losses) recorded in: |  |  |  |
Net income (loss) | 5 | (11) | 45 |
Other comprehensive income (loss) | 0 | 0 | 0 |
Purchases | 3 | 52 | 41 |
Sales | (4) | (2) | (89) |
Settlements | 0 | 0 | 0 |
Consolidations | 0 |  |  |
Deconsolidations | 219 |  | 219 |
Transfers out of Level 3 | 0 |  | 0 |
Fair value at end of period | 75 | 297 | 75 | 297
Change in unrealized gains/(losses) related to financial instruments held | 6 | (11) | 6 |
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) |  |  |  | 15
Other comprehensive income (loss) |  |  |  | 0
Purchases |  |  |  | 57
Sales |  |  |  | (14)
Settlements |  |  |  | 0
Consolidations |  |  |  | 0
Deconsolidations |  |  |  | 0
Fair value at end of period |  | 297 |  | 297
Change in unrealized gains/(losses) related to financial instruments held |  |  |  | 7
Consolidated Investment Vehicles | Corporate securities |  |  |  |
Fair Value Level 3 Rollforward |  |  |  |
Fair value at beginning of period | 84 | 90 | 96 | 91
Total pre-tax realized and unrealized gains (losses) recorded in: |  |  |  |
Net income (loss) | 0 | (2) | (3) | 4
Other comprehensive income (loss) | 0 | 0 | 0 | 0
Purchases | 0 | 1 | 6 | 2
Sales | 0 | (2) | (15) | (10)
Settlements | 0 | 0 | 0 | 0
Consolidations | 0 |  |  | 0
Deconsolidations | 84 |  | 84 | 0
Transfers out of Level 3 | 0 |  | 0 |
Fair value at end of period | 0 | 87 | 0 | 87
Change in unrealized gains/(losses) related to financial instruments held | 0 | (2) | 0 | 3
Consolidated Investment Vehicles | Structured products |  |  |  |
Fair Value Level 3 Rollforward |  |  |  |
Fair value at beginning of period | 0 | 38 | 46 | 0
Total pre-tax realized and unrealized gains (losses) recorded in: |  |  |  |
Net income (loss) | 7 | (3) | 9 | (6)
Other comprehensive income (loss) | 0 | 0 | 0 | 0
Purchases | 0 | 8 | 0 | 50
Sales | 0 | 0 | (48) | (21)
Settlements | 0 | 0 | 0 | 0
Consolidations | 0 |  |  | 0
Deconsolidations | (166) |  | (166) | 20
Transfers out of Level 3 | 0 |  | 0 |
Fair value at end of period | 173 | 43 | 173 | 43
Change in unrealized gains/(losses) related to financial instruments held | 7 | (3) | 7 | (6)
Other |  |  |  |
Fair Value Level 3 Rollforward |  |  |  |
Fair value at beginning of period | 33 | 37 | 50 | 27
Total pre-tax realized and unrealized gains (losses) recorded in: |  |  |  |
Net income (loss) | (20) | 1 | (33) | 12
Other comprehensive income (loss) | 0 | 0 | 0 | (1)
Purchases | 0 | 0 | 0 | 0
Sales | 0 | 0 | 0 | 0
Settlements | 0 | 0 | (4) | 0
Consolidations | 0 |  |  | 0
Deconsolidations | 0 |  | 0 | 0
Transfers out of Level 3 | 0 |  | 0 |
Fair value at end of period | 13 | 38 | 13 | 38
Change in unrealized gains/(losses) related to financial instruments held | (20) | 1 | (33) | 12
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 | 0 | 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 | (699) | (282) | (715) | (289)
Total Pretax Realized And Unrealized Gains (Losses) Recorded As Liabilities [Abstract] |  |  |  |
Net income (loss) | 17 | 8 | 18 | 34
Other comprehensive income (loss) | 13 | (4) | 14 | (1)
Issuances |  | 0 |  | 0
Sales |  | 0 |  | 0
Settlements | 127 | 27 | 141 | 92
Consolidations |  |  |  | (102)
Deconsolidations | 0 | 0 | 0 | 15
Fair value at end of period | (542) | (251) | (542) | (251)
Change in unrealized gains/(losses) included in earnings related to financial instruments | 9 | 8 | 11 | 57
Change in unrealized gains/(losses) included in OCI related to financial instruments | 13 | (4) | 14 | (1)
Liabilities of CIVs |  |  |  |
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Fair value at start of period | (4,199) | (3,987) | (4,154) | (3,705)
Total Pretax Realized And Unrealized Gains (Losses) Recorded As Liabilities [Abstract] |  |  |  |
Net income (loss) | 0 | (31) | (45) | 264
Other comprehensive income (loss) | 0 | 41 | (13) | 97
Issuances |  | (8) |  | (1,416)
Sales |  | 2 |  | 2
Settlements | 0 | 0 | 13 | 401
Consolidations |  |  |  | (26)
Deconsolidations | 4,199 | (26) | 4,199 | 374
Fair value at end of period | 0 | (4,009) | 0 | (4,009)
Change in unrealized gains/(losses) included in earnings related to financial instruments | 0 | (13) | 0 | 289
Change in unrealized gains/(losses) included in OCI related to financial instruments | 0 | 41 | 0 | 97
Obligations of state and political subdivisions | Fixed-maturity securities, available-for-sale |  |  |  |
Fair Value Level 3 Rollforward |  |  |  |
Fair value at beginning of period | 46 | 51 | 47 | 72
Total pre-tax realized and unrealized gains (losses) recorded in: |  |  |  |
Net income (loss) | 0 | 0 | 1 | 0
Other comprehensive income (loss) | (3) | (3) | (3) | (11)
Purchases | 0 | 0 | 0 | 0
Sales | 0 | 0 | 0 | 0
Settlements | (1) | 0 | (3) | (13)
Consolidations | 0 |  |  | 0
Deconsolidations | 0 |  | 0 | 0
Transfers out of Level 3 | (40) |  | (40) |
Fair value at end of period | 2 | 48 | 2 | 48
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 | 0 | (3) | 0 | (13)
RMBS | Fixed-maturity securities, available-for-sale |  |  |  |
Fair Value Level 3 Rollforward |  |  |  |
Fair value at beginning of period | 162 | 184 | 179 | 216
Total pre-tax realized and unrealized gains (losses) recorded in: |  |  |  |
Net income (loss) | 4 | 3 | 11 | 13
Other comprehensive income (loss) | (6) | (8) | (14) | (27)
Purchases | 0 | 22 | 0 | 22
Sales | 0 | 0 | 0 | 0
Settlements | (7) | (9) | (23) | (32)
Consolidations | 0 |  |  | 0
Deconsolidations | 0 |  | 0 | 0
Transfers out of Level 3 | 0 |  | 0 |
Fair value at end of period | 153 | 192 | 153 | 192
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 | (6) | (8) | (13) | (25)
Asset-backed securities | Fixed-maturity securities, available-for-sale |  |  |  |
Fair Value Level 3 Rollforward |  |  |  |
Fair value at beginning of period | 800 | 805 | 794 | 863
Total pre-tax realized and unrealized gains (losses) recorded in: |  |  |  |
Net income (loss) | 13 | 2 | 13 | 2
Other comprehensive income (loss) | (2) | 1 | (10) | (36)
Purchases | 0 | 4 | 23 | 39
Sales | 0 | (1) | (2) | (13)
Settlements | (15) | (5) | (22) | (49)
Consolidations | 0 |  |  | 0
Deconsolidations | 0 |  | 0 | 0
Transfers out of Level 3 | 0 |  | 0 |
Fair value at end of period | 796 | 806 | 796 | 806
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 | 3 | 1 | 0 | (35)
Credit Risk Contract |  |  |  |
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward] |  |  |  |
Fair value at start of period | (57) | (147) | (162) | (154)
Total pre-tax realized and unrealized gains (losses) recorded in: |  |  |  |
Net income (loss) | 9 | (48) | 115 | (42)
Other comprehensive income (loss) | 0 | 0 | 0 | 0
Issuances |  | 0 |  | 0
Sales |  | 0 |  | 0
Settlements | (1) | 1 | (2) | 2
Consolidations |  |  |  | 0
Deconsolidations | 0 | 0 | 0 | 0
Fair value at end of period | (49) | (194) | (49) | (194)
Change in unrealized gains/(losses) included in earnings related to financial instruments | $ 9 | $ (46) | $ 114 | $ (41)

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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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