Condensed Financial Information of HCI Group, Inc. - Statements of Cash Flows (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Cash flows from operating activities:
Net income	$ 62,664	$ 65,562	$ 30,157
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Stock-based compensation	8,110	5,365	844
Net realized investment (gain) loss	(4,735)	(80)	(276)
Depreciation and amortization	4,958	2,103	1,591
Loss from limited partnership investment	90
Deferred income taxes	(4,742)	557	(2,366)
Changes in operating assets and liabilities:
Other assets	(19,845)	(9,728)	(803)
Accrued expenses and other liabilities	9,770	3,381	(258)
Income taxes payable	(3,167)	(8,270)	3,857
Cash flows from investing activities:
Investment in limited partnership interest	(2,640)
Purchase of fixed-maturity securities	(83,365)	(82,907)	(10,128)
Purchase of equity securities	(44,257)	(11,308)	(6,410)
Purchase of property and equipment	(453)	(3,433)	(1,196)
Proceeds from sales of equity securities	16,810	2,809	1,735
Cash flows from financing activities:
Net proceeds from the issuance of common stock			20,082
Repurchases of common stock	(643)	(30,886)
Repurchases of common stock under share repurchase plan	(38,354)
Cash dividends paid to stockholders	(12,355)	(10,902)	(8,561)
Cash dividends received under share repurchase forward contract	685
Proceeds from exercise of stock options	125		283
Proceeds from exercise of stock warrants			11,869
Proceeds from issuance of long-term debt		143,250
Redemption of Series A preferred stock	(34)
Debt issuance costs paid	(234)	(4,770)	(35)
Tax benefits on stock-based compensation	2,080	1,060	1,161
Net (decrease) increase in cash and cash equivalents	21,318	63,184	129,859
Cash and cash equivalents at beginning of year	293,398	230,214	100,355
Cash and cash equivalents at end of year	314,716	293,398	230,214
HCI Group [Member]
Cash flows from operating activities:
Net income	62,664	65,562	30,157
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Stock-based compensation	5,502	2,362	237
Net realized investment (gain) loss	(309)	2
Depreciation and amortization	3,712	1,000	788
Loss from limited partnership investment	90
Equity in income of subsidiaries	(73,232)	(70,225)	(32,067)
Deferred income taxes	(2,058)	(914)	763
Changes in operating assets and liabilities:
Income taxes receivable	(814)	597	(2,379)
Other assets	629	(1,001)	84
Accrued expenses and other liabilities	1,116	1,136	(1,051)
Income taxes payable			(1,605)
Due to related parties	11,520	(6,338)	5,314
Net cash provided by (used in) operating activities	8,820	(7,819)	241
Cash flows from investing activities:
Investment in limited partnership interest	(2,640)
Purchase of fixed-maturity securities	(2,616)	(64)
Purchase of equity securities	(7,000)	(6,835)
Purchase of property and equipment	(277)	(262)	(668)
Proceeds from sales of equity securities	5,212	361
Dividends received from subsidiary		4,000	6,000
Investment in subsidiaries	(8,402)	(5,735)	(24,056)
Net cash used in investing activities	(15,723)	(8,535)	(18,724)
Cash flows from financing activities:
Net proceeds from the issuance of common stock			20,082
Repurchases of common stock	(643)	(30,886)
Repurchases of common stock under share repurchase plan	(38,354)
Cash dividends paid to stockholders	(12,355)	(10,902)	(8,561)
Cash dividends received under share repurchase forward contract	685
Proceeds from exercise of stock options	125		283
Proceeds from exercise of stock warrants			11,869
Proceeds from issuance of long-term debt		143,250
Redemption of Series A preferred stock	(34)
Debt issuance costs paid	(234)	(4,770)	(35)
Tax benefits on stock-based compensation	2,080	1,060	1,161
Net cash (used in) provided by financing activities	(48,730)	97,752	24,799
Net (decrease) increase in cash and cash equivalents	(55,633)	81,398	6,316
Cash and cash equivalents at beginning of year	87,715	6,317	1
Cash and cash equivalents at end of year	$ 32,082	$ 87,715	$ 6,317