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Financial Guaranty Variable Interest Entities and Consolidated Investment Vehicles - Schedule of Assets and Liabilities of Consolidated Investment Vehicles (Details) - USD ($) $ in Millions | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2022 | Dec. 31, 2023 | Dec. 31, 2021
Variable Interest Entity [Line Items] |  |  |
Cash | $ 107 | $ 97 | $ 120
Fixed-maturity securities, available-for-sale, at fair value, net of allowance for credit loss | 7,119 | 6,307 |
Other invested assets (includes $3 and $30, at fair value) | 133 | 829 |
Assets of consolidated investment vehicles (includes $331 and $5,363, at fair value) | 5,493 | 366 |
Short-term investments, at fair value | 810 | 1,661 |
Total assets | 16,843 | 12,539 |
Liabilities of consolidated investment vehicles (includes $0 and $4,431, at fair value) | 4,625 | 4 |
Financial guaranty variable interest entities’ liabilities, at fair value (with recourse $543 and $702, without recourse $11 and $13) | 715 | 554 |
Other liabilities | 457 | 435 |
Total liabilities | 11,551 | 6,774 |
Corporate securities |  |  |
Variable Interest Entity [Line Items] |  |  |
Fixed-maturity securities, available-for-sale, at fair value, net of allowance for credit loss | 2,084 | 2,141 |
Variable Interest Entity, Primary Beneficiary | Consolidated Investment Vehicles |  |  |
Variable Interest Entity [Line Items] |  |  |
Liabilities of consolidated investment vehicles (includes $0 and $4,431, at fair value) | 4,090 | 0 |
Financial guaranty variable interest entities’ liabilities, at fair value (with recourse $543 and $702, without recourse $11 and $13) | 313 | 0 |
Due to brokers and counterparties | 112 | 0 |
Other liabilities | 110 | 4 |
Total liabilities | 4,625 | 4 |
Variable Interest Entity, Primary Beneficiary | Consolidated Investment Vehicles | Affiliated Entity |  |  |
Variable Interest Entity [Line Items] |  |  |
Total liabilities |  | 3 |
Variable Interest Entity, Primary Beneficiary | Consolidated Investment Vehicles |  |  |
Variable Interest Entity [Line Items] |  |  |
Cash | 38 | 0 |
Other invested assets (includes $3 and $30, at fair value) | 1 | 0 |
Due from brokers and counterparties | 32 | 0 |
Total assets | 5,493 | 366 |
Redeemable noncontrolling interest | 21 |  |
Variable Interest Entity, Primary Beneficiary | Consolidated Investment Vehicles | Investments in AssuredIM Funds and Other Affiliated Entities |  |  |
Variable Interest Entity [Line Items] |  |  |
Total assets | $ 392 |  |
Variable Interest Entity, Primary Beneficiary | Consolidated Investment Vehicles | Investments in Other Affiliated Entities |  |  |
Variable Interest Entity [Line Items] |  |  |
Total assets |  | 281 |
Variable Interest Entity, Primary Beneficiary | Consolidated Investment Vehicles | CLO obligations, FVO |  |  |
Variable Interest Entity [Line Items] |  |  |
CLOs, weighted average maturity | 6 years 2 months 12 days |  |
CLOs, weighted average interest rate | 5.30% |  |
Variable Interest Entity, Primary Beneficiary | Consolidated Investment Vehicles | Warehouse financing debt |  |  |
Variable Interest Entity [Line Items] |  |  |
CLOs, weighted average maturity | 1 year 10 months 24 days |  |
CLOs, weighted average interest rate | 4.50% |  |
Variable Interest Entity, Primary Beneficiary | Consolidated Investment Vehicles | Fund Investments |  |  |
Variable Interest Entity [Line Items] |  |  |
Cash | $ 59 | 35 |
Variable Interest Entity, Primary Beneficiary | Consolidated Investment Vehicles | Equity securities and warrants |  |  |
Variable Interest Entity [Line Items] |  |  |
Fixed-maturity securities, available-for-sale, at fair value, net of allowance for credit loss | 434 | 83 |
Variable Interest Entity, Primary Beneficiary | Consolidated Investment Vehicles | Structured products |  |  |
Variable Interest Entity [Line Items] |  |  |
Fixed-maturity securities, available-for-sale, at fair value, net of allowance for credit loss | 128 | 248 |
Variable Interest Entity, Primary Beneficiary | Consolidated Investment Vehicles | Corporate securities |  |  |
Variable Interest Entity [Line Items] |  |  |
Fixed-maturity securities, available-for-sale, at fair value, net of allowance for credit loss | 96 | 0 |
Variable Interest Entity, Primary Beneficiary | Consolidated Investment Vehicles | Loans in CLOs and CLO warehouses, FVO |  |  |
Variable Interest Entity [Line Items] |  |  |
Assets of consolidated investment vehicles (includes $331 and $5,363, at fair value) | 4,570 | 0 |
Variable Interest Entity, Primary Beneficiary | Consolidated Investment Vehicles | Short-term investments |  |  |
Variable Interest Entity [Line Items] |  |  |
Short-term investments, at fair value | 135 | $ 0 |
Voting Interest Entity | Consolidated Investment Vehicles |  |  |
Variable Interest Entity [Line Items] |  |  |
Total assets | 58 |  |
Total liabilities | $ 1 |  |

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