Condensed Financial Information of HCI Group, Inc. - Statements of Income (Detail) - USD ($) $ in Thousands	3 Months Ended												12 Months Ended
	Dec. 31, 2022	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Dec. 31, 2021	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Condensed Financial Statements Captions [Line Items]
Net investment income (loss)													$ 32,447	$ 12,335	$ 4,564
Net realized investment (losses) gains													(1,187)	6,472	1,000
Net unrealized investment (losses) gains													(7,153)	1,363	679
Credit loss expense													0	0	611
Other income													4,488	6,447	1,854
Loss on repurchases of convertible senior notes													0	0	(150)
Interest expense	$ (2,839)	$ (2,813)	$ (1,515)	$ (601)	$ (657)	$ (1,664)	$ (2,000)	$ (2,079)	$ (2,888)	$ (2,856)	$ (3,020)	$ (2,970)	(7,768)	(6,400)	(11,734)
Debt conversion expense													0	(1,754)	0
Income tax benefit													13,815	(3,991)	(9,348)
Equity in (loss) income of subsidiaries													495	417	(57)
Net (loss) income after noncontrolling interests													(58,511)	1,856	27,580
HCI Group [Member]
Condensed Financial Statements Captions [Line Items]
Net investment income (loss)													5,498	3,115	(676)
Net realized investment (losses) gains													(1,154)	3,344	330
Net unrealized investment (losses) gains													(1,609)	92	229
Credit loss expense													0	0	(20)
Other income													1,138	222	0
Loss on repurchases of convertible senior notes													0	0	(150)
Interest expense													(6,876)	(5,467)	(10,710)
Debt conversion expense													0	(1,754)	0
Operating expenses													(9,877)	(9,056)	(6,887)
Loss before income tax benefit and equity in (loss) income of subsidiaries													(12,880)	(9,504)	(17,884)
Income tax benefit													1,700	2,086	4,024
Net loss before equity in (loss) income of subsidiaries													(11,180)	(7,418)	(13,860)
Equity in (loss) income of subsidiaries													(47,331)	9,274	41,440
Net (loss) income after noncontrolling interests													$ (58,511)	$ 1,856	$ 27,580