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Significant Transactions - Outrigger Re (Details) - USD ($) $ in Millions |  | 3 Months Ended
--- | --- | ---
Dec. 20, 2022 | Dec. 31, 2022
Outrigger Re |  |
Other Significant Transactions [Line Items] |  |
Issuance of redeemable preference shares | $ 250.0 |
Outrigger Re |  |
Other Significant Transactions [Line Items] |  |
Ownership interest after all transactions (as a percent) |  | 100.00%
Purchase price |  | $ 205.0

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