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Significant Transactions - Bamboo (Details) - USD ($) $ in Millions |  | 3 Months Ended |
--- | --- | --- | ---
Jan. 02, 2024 | Dec. 31, 2023 | Mar. 31, 2024
Bamboo Ide8 Insurance Services LLC |  |  |
Other Significant Transactions [Line Items] |  |  |
Assets and goodwill acquired | $ 479.5 |  |
Liabilities acquired | 91.7 |  |
Noncontrolling interest acquired | 111.1 |  |
Total goodwill and other intangible assets | 371.4 |  |
Transaction costs | 4.0 |  | $ 0.3
Bamboo Ide8 Insurance Services LLC |  |  |
Other Significant Transactions [Line Items] |  |  |
Contributions to subsidiaries | 296.7 |  |
Contribution of primary capital | 36.0 |  |
Cash contributions for transaction | $ 20.0 |  |
Basic ownership | 72.80% |  |
Ownership percentage, after equity incentives | 63.70% |  |
Bamboo Ide8 Insurance Services LLC | Bamboo Management |  |  |
Other Significant Transactions [Line Items] |  |  |
Basic ownership | 16.10% |  |
Ownership percentage, after equity incentives | 26.60% |  |
Outrigger Re |  |  |
Other Significant Transactions [Line Items] |  |  |
Contributions to subsidiaries |  | $ 205.0 |

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