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Business and Basis of Presentation - Additional Information (Details) | Jul. 01, 2023 | Mar. 31, 2026 company | Jan. 21, 2026 business
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Long-Lived Assets Held-for-sale [Line Items] |  |  |
Number of businesses reinsured | business |  |  | 2
Number of holding companies with outstanding public debt | company |  | 2 |
Assured Life Re Acquisition |  |  |
Long-Lived Assets Held-for-sale [Line Items] |  |  |
Voting equity interest acquired, percentage |  |  | 100.00%
Sound Point Capital Management, LP |  |  |
Long-Lived Assets Held-for-sale [Line Items] |  |  |
Ownership interest | 0.30 |  |

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