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Reinsurance - Schedule of ILN Transactions and XOL Transactions (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Oct. 26, 2021	Apr. 27, 2021
Reinsurance Policy, Type [Axis]: 2021-1 ILN
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Percentage of population with production prior to period start date (in percent)	1.00%
Reinsurance Policy, Type [Axis]: 2021-1 ILN Transaction
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Initial Reinsurance Coverage			$ 367,238
Current Reinsurance Coverage	$ 101,337
Initial First Layer Retained Loss			$ 163,708
Current First Layer Retained Loss	$ 162,246
Reinsurance Policy, Type [Axis]: 2021-2 ILN
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Percentage of population with production prior to period start date (in percent)	2.00%
Reinsurance Policy, Type [Axis]: 2021-2 ILN Transaction
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Initial Reinsurance Coverage		$ 363,596
Current Reinsurance Coverage	$ 188,327
Initial First Layer Retained Loss		$ 146,229
Current First Layer Retained Loss	144,446
Reinsurance Policy, Type [Axis]: 2022-1 XOL Transaction
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Initial Reinsurance Coverage	289,741
Current Reinsurance Coverage	156,776
Initial First Layer Retained Loss	133,366
Current First Layer Retained Loss	$ 130,371
Percentage of population with production prior to period start date (in percent)	1.00%
Reinsurance Policy, Type [Axis]: 2022-2 XOL Transaction
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Initial Reinsurance Coverage	$ 154,306
Current Reinsurance Coverage	111,008
Initial First Layer Retained Loss	78,906
Current First Layer Retained Loss	$ 74,989
Percentage of population with production prior to period start date (in percent)	1.00%
Reinsurance Policy, Type [Axis]: 2022-3 XOL Transaction
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Initial Reinsurance Coverage	$ 96,779
Current Reinsurance Coverage	71,976
Initial First Layer Retained Loss	106,265
Current First Layer Retained Loss	102,730
Reinsurance Policy, Type [Axis]: 2023-1 XOL Transaction
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Initial Reinsurance Coverage	89,864
Current Reinsurance Coverage	66,578
Initial First Layer Retained Loss	146,513
Current First Layer Retained Loss	143,341
Reinsurance Policy, Type [Axis]: 2023-2 XOL Transaction
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Initial Reinsurance Coverage	100,777
Current Reinsurance Coverage	77,129
Initial First Layer Retained Loss	136,875
Current First Layer Retained Loss	136,070
Reinsurance Policy, Type [Axis]: 2024 XOL Transaction
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Initial Reinsurance Coverage	162,500
Current Reinsurance Coverage	162,500
Initial First Layer Retained Loss	312,172
Current First Layer Retained Loss	312,057
Reinsurance Policy, Type [Axis]: 2025 XOL Transaction
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Initial Reinsurance Coverage	206,217
Current Reinsurance Coverage	206,217
Initial First Layer Retained Loss	233,783
Current First Layer Retained Loss	$ 233,783

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