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v3.23.2

Municipal Bond Guarantee Insurance - Narrative (Details) - USD ($) | 1 Months Ended | 3 Months Ended | 6 Months Ended | 12 Months Ended |  |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Dec. 31, 2022 | Jun. 30, 2023 | Jun. 30, 2022 | Jun. 30, 2023 | Jun. 30, 2022 | Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2018 | Jan. 01, 2025 | Dec. 31, 2023 | Mar. 31, 2021 | Jun. 30, 2018 | Jul. 31, 2012
Guarantor Obligations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Percentage of risk premium ceded |  | 60.00% |  | 60.00% |  |  |  |  |  |  |  |  |
Insurance-linked securities, term |  |  |  |  |  | 12 years | 12 years | 12 years |  |  |  |  |
Insurance-linked securities, callable term |  |  |  |  |  | 7 years | 5 years | 5 years |  |  |  |  |
HG Global |  |  |  |  |  |  |  |  |  |  |  |  |
Guarantor Obligations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Collateral held in supplement trust | $ 856,900,000 | $ 892,400,000 |  | $ 892,400,000 |  | $ 856,900,000 |  |  |  |  |  |  |
Collateral trusts, investments and cash | 503,300,000 | 525,700,000 |  | 525,700,000 |  | 503,300,000 |  |  |  |  |  |  |
BAM |  |  |  |  |  |  |  |  |  |  |  |  |
Guarantor Obligations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Surplus notes | 340,000,000 | 340,000,000 |  | 340,000,000 |  | 340,000,000 |  |  |  |  |  |  |
Interest receivable | 13,600,000 | 26,700,000 |  | 26,700,000 |  | 13,600,000 |  |  |  |  |  |  |
Series A BAM Surplus Note | BAM |  |  |  |  |  |  |  |  |  |  |  |  |
Guarantor Obligations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Interest receivable | 157,900,000 | 171,000,000 |  | 171,000,000 |  | 157,900,000 |  |  |  |  |  |  |
HG Global |  |  |  |  |  |  |  |  |  |  |  |  |
Guarantor Obligations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Surplus notes |  | $ 503,000,000 |  | $ 503,000,000 |  |  |  |  |  |  |  |  | $ 503,000,000
Percentage of par value of policy reinsured |  | 15.00% |  | 15.00% |  |  |  |  |  |  |  |  |
Percent over a target trust balance |  |  |  | 102.00% |  |  |  |  |  |  |  |  |
Supplement trust target |  | $ 603,000,000 |  | $ 603,000,000 |  |  |  |  |  |  |  |  |
HG Global | Series A BAM Surplus Note |  |  |  |  |  |  |  |  |  |  |  |  |
Guarantor Obligations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Assets Held-in-trust | 568,300,000 | $ 585,600,000 |  | 585,600,000 |  | 568,300,000 |  |  |  |  |  |  |
HG Global | BAM | Maximum |  |  |  |  |  |  |  |  |  |  |  |  |
Guarantor Obligations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Reinsurance, Excess Retention, Amount Reinsured, Per Life |  |  |  | $ 125,000,000 |  |  |  |  |  |  |  |  |
HG Re |  |  |  |  |  |  |  |  |  |  |  |  |
Guarantor Obligations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Percentage of par value of policy reinsured |  | 15.00% |  | 15.00% |  |  |  |  |  |  |  |  |
Assets Held-in-trust | 288,600,000 | $ 306,800,000 |  | $ 306,800,000 |  | 288,600,000 |  |  |  |  |  |  |
BAM | Surplus Note |  |  |  |  |  |  |  |  |  |  |  |  |
Guarantor Obligations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Repayments of unsecured debt | 36,000,000 | $ 0 | $ 0 | $ 0 | $ 0 |  |  |  |  |  |  |  |
Accrued interest payment on surplus notes | 10,400,000 |  |  |  |  | 10,400,000 |  |  |  |  |  |  |
BAM | Supplemental Trust |  |  |  |  |  |  |  |  |  |  |  |  |
Guarantor Obligations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Repayments of unsecured debt | 24,600,000 |  |  |  |  |  |  |  |  |  |  |  |
Accrued interest payment on surplus notes | 1,000,000 |  |  |  |  | 1,000,000 |  |  |  |  |  |  |
BAM | US Treasury (UST) Interest Rate | Surplus Note |  |  |  |  |  |  |  |  |  |  |  |  |
Guarantor Obligations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Basis spread on variable rate |  |  |  | 3.00% |  |  |  |  |  |  |  |  |
BAM | Forecast | US Treasury (UST) Interest Rate | Surplus Note |  |  |  |  |  |  |  |  |  |  |  |  |
Guarantor Obligations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Effective percentage |  |  |  |  |  |  |  |  |  | 7.70% |  |  |
BAM | Forecast | Fixed interest rate | Surplus Note |  |  |  |  |  |  |  |  |  |  |  |  |
Guarantor Obligations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Derivative, fixed interest rate (as a percent) |  |  |  |  |  |  |  |  | 8.00% |  |  |  |
BAM | Fidus Re Ltd. |  |  |  |  |  |  |  |  |  |  |  |  |
Guarantor Obligations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Secured debt | $ 150,000,000 |  |  |  |  | 150,000,000 |  |  |  |  | $ 150,000,000 | $ 100,000,000 |
Reinsurance, Limit on Total Reimbursement |  |  |  |  |  | 150,000,000 | $ 150,000,000 | $ 100,000,000 |  |  |  |  |
Percentage of financial guaranty policies covered |  |  |  | 31.00% |  |  |  |  |  |  |  |  |
BAM | Fidus Re Ltd. | 2018 Covered Portfolio |  |  |  |  |  |  |  |  |  |  |  |  |
Guarantor Obligations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Percentage of financial guaranty policies covered |  |  |  | 26.00% |  |  |  |  |  |  |  |  |
BAM | Fidus Re Ltd. | 2021 Covered Portfolio |  |  |  |  |  |  |  |  |  |  |  |  |
Guarantor Obligations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Percentage of financial guaranty policies covered |  |  |  | 30.00% |  |  |  |  |  |  |  |  |
BAM | Fidus Re Ltd. | Maximum |  |  |  |  |  |  |  |  |  |  |  |  |
Guarantor Obligations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Reinsurance, Excess Retention, Amount Reinsured, Per Life |  |  |  |  |  | 276,700,000 | 301,700,000 | 276,100,000 |  |  |  |  |
BAM | Fidus Re Ltd. | Minimum |  |  |  |  |  |  |  |  |  |  |  |  |
Guarantor Obligations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Reinsurance, Excess Retention, Amount Reinsured, Per Life |  |  |  |  |  | $ 110,000,000 | $ 135,000,000 | $ 165,000,000 |  |  |  |  |
Fidus Re Ltd. | BAM |  |  |  |  |  |  |  |  |  |  |  |  |
Guarantor Obligations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Percentage of par value of policy reinsured |  |  |  |  |  | 90.00% | 90.00% | 90.00% |  |  |  |  |

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