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Comprehensive Income - Schedule of Amounts Reclassed Out of Each Component of Accumulated Other Comprehensive Income (Details) - USD ($) $ in Thousands | 3 Months Ended |
--- | --- | ---
Mar. 31, 2026 | Mar. 31, 2025 | Dec. 31, 2025
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items] |  |  |
Income tax expense (benefit) | $ 481 | $ 617 |
Other Comprehensive Income (Loss), Financial Liability, Fair Value Option, Unrealized Gain (Loss) Arising During Period, after Tax | 0 | 442 |
Net of tax and noncontrolling interest | (6,851) | (46,391) |
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax | 3 | 4,901 |
Realized Investment Gains (Losses) | 3 | (3) |
Allowance for Credit Loss, Receivable, Other, Current | 350 |  | $ 350
Unrealized Gains (Losses) on Available-for-Sale Securities [Member] |  |  |
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items] |  |  |
Net of tax and noncontrolling interest | 3 | 4,459 |
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax | 3 | 4,459 |
Realized Investment Gains (Losses) | 3 | 5,957 |
Accumulated Gain (Loss), Financial Liability, Fair Value Option, Attributable to Parent [Member] |  |  |
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items] |  |  |
Other Comprehensive Income (Loss), Financial Liability, Fair Value Option, Unrealized Gain (Loss) Arising During Period, after Tax | 0 | (442) |
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax | 0 | 442 |
Other Comprehensive Income (Loss), Financial Liability, Fair Value Option, before Tax, after Reclassification Adjustment | 0 | 589 |
Accumulated Translation Adjustment [Member] |  |  |
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items] |  |  |
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax | 0 | 0 |
Accumulated Translation Adjustment [Member] | Discontinued Operations, Disposed of by Sale | Ambac Assurance Corporation [Member] |  |  |
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items] |  |  |
Credit Risk Changes of Fair Value, Net Loss on Discontinued Operation | 0 |  |
Reclassification out of Accumulated Other Comprehensive Income [Member] |  |  |
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items] |  |  |
Net of tax and noncontrolling interest | 3 | 4,901 |
Reclassification out of Accumulated Other Comprehensive Income [Member] | Unrealized Gains (Losses) on Available-for-Sale Securities [Member] |  |  |
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items] |  |  |
Income tax expense (benefit) | 0 | 1,498 |
Reclassification out of Accumulated Other Comprehensive Income [Member] | Accumulated Gain (Loss), Financial Liability, Fair Value Option, Including Portion Attributable to Noncontrolling Interest [Member] |  |  |
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items] |  |  |
Income tax expense (benefit) | $ 0 | $ 147 |

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