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Fair Value Measurement - Fair Value Level 3 Rollforward Recurring Basis (Details) - USD ($) $ in Millions | 3 Months Ended
--- | ---
Mar. 31, 2025 | Mar. 31, 2024
FG VIEs’ Assets |  |
Fair Value Level 3 Rollforward |  |
Fair value at beginning of period | $ 147 | $ 174
Total pre-tax realized and unrealized gains (losses) recorded in: |  |
Net income (loss) | 3 | (2)
Other comprehensive income (loss) | 0 | 1
Purchases | 0 | 0
Sales | 0 | 0
Settlements | (5) | (6)
Transfers into Level 3 |  | 0
Fair value at end of period | 145 | 167
Change in unrealized gains/(losses) related to financial instruments held | 2 | (3)
Consolidated Investment Vehicles | Assets of CIVs, Equity Securities |  |
Fair Value Level 3 Rollforward |  |
Fair value at beginning of period | 99 | 80
Total pre-tax realized and unrealized gains (losses) recorded in: |  |
Net income (loss) | 19 | 8
Other comprehensive income (loss) | 0 | 0
Purchases | 0 | 0
Sales | 0 | (2)
Settlements | 0 | 0
Transfers into Level 3 |  | (3)
Fair value at end of period | 118 | 89
Change in unrealized gains/(losses) related to financial instruments held | 19 | 7
Consolidated Investment Vehicles | Structured Products |  |
Fair Value Level 3 Rollforward |  |
Fair value at beginning of period |  | 189
Total pre-tax realized and unrealized gains (losses) recorded in: |  |
Net income (loss) |  | 4
Other comprehensive income (loss) |  | 0
Purchases |  | 29
Sales |  | (12)
Settlements |  | 0
Transfers into Level 3 |  | (10)
Fair value at end of period |  | 220
Change in unrealized gains/(losses) related to financial instruments held |  | 5
Other |  |
Fair Value Level 3 Rollforward |  |
Fair value at beginning of period | 5 | 14
Total pre-tax realized and unrealized gains (losses) recorded in: |  |
Net income (loss) | 2 | (10)
Other comprehensive income (loss) | (1) | 1
Purchases | 0 | 0
Sales | 0 | 0
Settlements | 0 | 0
Transfers into Level 3 |  | 0
Fair value at end of period | 6 | 5
Change in unrealized gains/(losses) related to financial instruments held | 2 | (10)
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 | (1) | 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 | (164) | (554)
Total pre-tax realized and unrealized gains (losses) recorded in: |  |
Net income (loss) | (2) | 9
Other comprehensive income (loss) | (1) | (2)
Settlements | 4 | 148
Fair value at end of period | (163) | (399)
Change in unrealized gains/(losses) included in earnings related to financial instruments | (2) | 2
Change in unrealized gains/(losses) included in OCI related to financial instruments | (1) | (2)
Obligations of state and political subdivisions | Fixed-maturity securities, available-for-sale |  |
Fair Value Level 3 Rollforward |  |
Fair value at beginning of period | 10 | 6
Total pre-tax realized and unrealized gains (losses) recorded in: |  |
Net income (loss) | 0 | 0
Other comprehensive income (loss) | 0 | 0
Purchases | 0 | 0
Sales | 0 | 0
Settlements | 0 | 0
Transfers into Level 3 |  | 0
Fair value at end of period | 10 | 6
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 | 6 | 0
Corporate securities | Fixed-maturity securities, available-for-sale |  |
Fair Value Level 3 Rollforward |  |
Fair value at beginning of period | 0 |
Total pre-tax realized and unrealized gains (losses) recorded in: |  |
Net income (loss) | 0 |
Other comprehensive income (loss) | 0 |
Purchases | 5 |
Sales | 0 |
Settlements | 0 |
Fair value at end of period | 5 |
Corporate 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 | 0 |
RMBS | Fixed-maturity securities, available-for-sale |  |
Fair Value Level 3 Rollforward |  |
Fair value at beginning of period | 145 | 154
Total pre-tax realized and unrealized gains (losses) recorded in: |  |
Net income (loss) | 3 | 3
Other comprehensive income (loss) | 2 | 1
Purchases | 0 | 0
Sales | 0 | 0
Settlements | (6) | (5)
Transfers into Level 3 |  | 0
Fair value at end of period | 144 | 153
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 | (53) | 1
Asset-backed securities | Fixed-maturity securities, available-for-sale |  |
Fair Value Level 3 Rollforward |  |
Fair value at beginning of period | 1,031 | 803
Total pre-tax realized and unrealized gains (losses) recorded in: |  |
Net income (loss) | 7 | 16
Other comprehensive income (loss) | 1 | 2
Purchases | 0 | 10
Sales | (9) | 0
Settlements | (47) | (30)
Transfers into Level 3 |  | (20)
Fair value at end of period | 983 | 821
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 | (1) | 2
Fixed-Maturity Securities, Trading | Fixed-maturity securities, available-for-sale |  |
Fair Value Level 3 Rollforward |  |
Fair value at beginning of period | 5 |
Total pre-tax realized and unrealized gains (losses) recorded in: |  |
Net income (loss) | 0 |
Other comprehensive income (loss) | 0 |
Purchases | 0 |
Sales | 0 |
Settlements | 0 |
Fair value at end of period | 5 |
Change in unrealized gains/(losses) related to financial instruments held | (1) |
Credit Risk Contract |  |
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward] |  |
Fair value at start of period | (29) | (50)
Total pre-tax realized and unrealized gains (losses) recorded in: |  |
Net income (loss) | 104 | 10
Other comprehensive income (loss) | 0 | 0
Settlements | (105) | 1
Fair value at end of period | (30) | (39)
Change in unrealized gains/(losses) included in earnings related to financial instruments | $ (1) | $ 4

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