Reinsurance - Effects of reinsurance on premiums written and earned (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	$ 130,952	$ 137,047	$ 349,365	$ 349,084
Ceded premiums, written	30,358	(119,131)	(34,763)	(297,693)
Net premiums, written	161,310	17,916	314,602	51,391
Direct premiums, earned	117,032	105,245	348,253	282,645
Ceded premiums, earned	(41,846)	(93,982)	(188,686)	(248,804)
Net premiums, earned	$ 75,186	$ 11,263	$ 159,567	$ 33,841