Reinsurance - Reinsurance Arrangements (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Reinsurance Disclosures [Abstract]
Direct premiums written	$ 531,988	$ 500,677	$ 1,489,216	$ 1,429,685
Ceded premiums written	2,717
Ceded premiums written		(23,956)	(573,539)	(670,339)
Net premiums written	534,705	476,721	915,677	759,346
Direct premiums earned	474,311	452,450	1,393,003	1,295,858
Ceded premiums earned	(143,271)	(161,819)	(476,465)	(459,102)
Premiums earned, net	331,040	290,631	916,538	836,756
Direct losses and loss adjustment expenses	308,860	1,269,344	770,161	1,724,729
Ceded losses and loss adjustment expenses	(20,888)	(938,900)	(52,308)	(1,008,875)
Net losses and loss adjustment expenses	$ 287,972	$ 330,444	$ 717,853	$ 715,854

Amount of earned premiums ceded to other entities.

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