Reinsurance - Additional Information (Detail) $ in Thousands			1 Months Ended	3 Months Ended	9 Months Ended	12 Months Ended
		Oct. 26, 2023 USD ($)	Oct. 31, 2022 USD ($)	Dec. 31, 2022 USD ($) Reinsurer	Sep. 30, 2022 USD ($)	Dec. 31, 2023 USD ($) Reinsurer	Dec. 31, 2022 USD ($) Reinsurer	Dec. 31, 2021 USD ($)
Reinsurance Premiums For Insurance Companies By Product Segment [Line Items]
Percentage of ceding commission on ceded premiums written						30.00%
Profit Commission On Net Profit						10.00%
Number of reinsurers | Reinsurer				45		33	45
Reinsurance recoverable				$ 688,359		$ 350,294	$ 688,359
Assumed premiums written						$ 135,816	$ 12,916	$ 128,948
Percentage of assumed premiums to net premium earned						6.18%	15.80%	26.11%
Ceded losses recognized as a reduction in losses and loss adjustment expenses						$ 94,863	$ 812,623	$ 40,432
Proceeds from Collection of Other Receivables		$ 4,875
Increase in credit loss expense						(336)	364	5
Allowances for credit losses related to the reinsurance recoverable balance				454		118	454
Payment for reinstatement premiums							6,684
Write-off of reinsurance premiums				3,306
Net increase in premiums ceded					$ 12,600
Funds Held under Reinsurance Agreements, Liability						30,087
Reduction in premiums ceded						27,972	18,710	10,864
Reinsurance payable on paid losses and loss adjustment expenses				8,606		3,145	8,606
Premiums Receivable, Net				34,998		38,037	34,998
Assumed premiums receivable						19,954	0	0
Premium Refund From Reinsurance Contract			$ 5,457
Other assets	[1]			31,671		50,365	31,671
Benefits receivable related to retrospective reinsurance contracts				16,317		44,289	16,317
Funds withheld for assumed business				48,772		30,087	48,772
United Insurance Holdings Corporation [Member]
Reinsurance Premiums For Insurance Companies By Product Segment [Line Items]
Net amount due to entity						4,784
Funds withheld for assumed business				48,772		30,087	48,772
Citizens [Member]
Reinsurance Premiums For Insurance Companies By Product Segment [Line Items]
Assumed premiums written						143,087
Hurricane Ian [Member]
Reinsurance Premiums For Insurance Companies By Product Segment [Line Items]
Ceded losses recognized as a reduction in losses and loss adjustment expenses						104,614	782,071
Hurricane Irma [Member]
Reinsurance Premiums For Insurance Companies By Product Segment [Line Items]
Ceded losses recognized as a reduction in losses and loss adjustment expenses							20,000	32,144
Tropical Storm Eta [Member]
Reinsurance Premiums For Insurance Companies By Product Segment [Line Items]
Ceded losses recognized as a reduction in losses and loss adjustment expenses						4,301
Hurricane Michael [Member]
Reinsurance Premiums For Insurance Companies By Product Segment [Line Items]
Ceded losses recognized as a reduction in losses and loss adjustment expenses								4,434
Hurricane Sally [Member]
Reinsurance Premiums For Insurance Companies By Product Segment [Line Items]
Ceded losses recognized as a reduction in losses and loss adjustment expenses						5,416	10,483	3,854
Northeast Region Member | United Insurance Holdings Corporation [Member]
Reinsurance Premiums For Insurance Companies By Product Segment [Line Items]
Assumed premiums written						0	(27,488)	93,607
Net amount payable				1,581		581	1,581
Ceding commission payable				581		581	581
Reinsurance payable on paid losses and loss adjustment expenses				1,000			1,000
Southeast Region Member
Reinsurance Premiums For Insurance Companies By Product Segment [Line Items]
Proceeds from Collection of Other Receivables						4,875
Net Withdrawal From Funds Held Under Reinsurance Agreement						13,482
Southeast Region Member | United Insurance Holdings Corporation [Member]
Reinsurance Premiums For Insurance Companies By Product Segment [Line Items]
Assumed premiums written						(7,271)	40,404	$ 35,341
Net amount payable				7,521		4,203	7,521
Ceding commission payable				16			16
Assumed premiums written payable						1,712
Reinsurance payable on paid losses and loss adjustment expenses				$ 7,606		2,765	7,606
Assumed premiums receivable						101
Ceding commission receivable						274
Other Non-catastrophe Claims [Member]
Reinsurance Premiums For Insurance Companies By Product Segment [Line Items]
Ceded losses recognized as a reduction in losses and loss adjustment expenses						34	$ 69
Unearned Premiums [Member]
Reinsurance Premiums For Insurance Companies By Product Segment [Line Items]
Net Withdrawal From Funds Held Under Reinsurance Agreement						7,496
Losses and L A E [Member]
Reinsurance Premiums For Insurance Companies By Product Segment [Line Items]
Net Withdrawal From Funds Held Under Reinsurance Agreement						2,310
Claims Handling Fees [Member]
Reinsurance Premiums For Insurance Companies By Product Segment [Line Items]
Net Withdrawal From Funds Held Under Reinsurance Agreement						4,875
Ceding Commission [Member]
Reinsurance Premiums For Insurance Companies By Product Segment [Line Items]
Net Withdrawal From Funds Held Under Reinsurance Agreement						$ 1,199
Reinsurance Recoverable [Member] | Reinsurance [Member] | Reinsurer Concentration Risk [Member]
Reinsurance Premiums For Insurance Companies By Product Segment [Line Items]
Percentage of reinsurance recoverable major reinsurers						67.10%

[1] See Note 16 for details of balances associated with variable interest entity.