Schedule II - Condensed Financial Information of Registrant - Condensed Statements of Cash Flows (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Cash flow from operating activities [Abstract]
Net income (loss)	$ (78,158)	$ 1,011	$ 14,710
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Depreciation and amortization	1,904	1,477	1,385
Amortization of investment premium or discount, net	3,740	916	1,546
Loss (gain) on early extinguishment of debt	0	3,575	0
Share-based compensation	1,580	2,176	2,367
Changes in operating assets and liabilities [Abstract]
Current and deferred income taxes, net	(32,835)	(3,723)	6,109
Other	10,285	602	(1,444)
Net cash provided by (used in) operating activities	(91,908)	35,316	30,270
Cash flow from investing activities [Abstract]
Payment for acquisition	0	10,402	0
Purchases of property and equipment	(3,357)	(2,040)	(2,026)
Net cash provided by (used in) investing activities	76,367	(9,011)	(21,184)
Net Cash Provided by (Used in) Financing Activities, Continuing Operations [Abstract]
Proceeds from issuance of long-term debt, net of issuance costs	0	98,390	0
Payment of long-term debt and prepayment penalties	0	(48,000)	(5,000)
Issuance of common stock for share-based awards	42	1	39
Purchases of FedNat Holding Company common stock	(10,418)	(3,449)	(5,061)
Dividends paid	(5,077)	(4,309)	(4,184)
Net cash provided by (used in) financing activities	(15,453)	42,633	(30,891)
Net increase (decrease) in cash and cash equivalents	(30,994)	68,938	(21,805)
Cash and cash equivalents at beginning-of-period	133,361	64,423	86,228
Cash and cash equivalents at end-of-period	102,367	133,361	64,423
Parent Company
Cash flow from operating activities [Abstract]
Net income (loss)	(78,158)	1,011	14,710
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Net realized and unrealized investment (gains) losses	(972)	(448)	765
Depreciation and amortization	94,363	(20,909)	(30,895)
Amortization of investment premium or discount, net	430	369	141
Loss (gain) on early extinguishment of debt	0	3,575	0
Share-based compensation	790	1,050	1,183
Changes in operating assets and liabilities [Abstract]
Current and deferred income taxes, net	6,900	(5,379)	(2,371)
Due to subsidiaries	(21,891)	3,044	(9,317)
Other	3,564	998	1,497
Net cash provided by (used in) operating activities	5,026	(16,689)	(24,287)
Cash flow from investing activities [Abstract]
Capital contributions to consolidated subsidiaries	(11,000)	0	(30,000)
Sales, maturities and redemptions of investments securities	31,300	11,276	54,543
Purchases of investment securities	(25,089)	(15,617)	(61,009)
Payment for acquisition	0	(25,566)	0
Issuance of note receivable to subsidiary	0	(18,000)	0
Purchases of property and equipment	(21)	(289)	(639)
Net cash provided by (used in) investing activities	(4,810)	(48,196)	(37,105)
Net Cash Provided by (Used in) Financing Activities, Continuing Operations [Abstract]
Proceeds from issuance of long-term debt, net of issuance costs	0	98,390	0
Payment of long-term debt and prepayment penalties	0	(48,000)	0
Issuance of common stock for share-based awards	42	1	39
Purchases of FedNat Holding Company common stock	(10,418)	(3,449)	(5,061)
Dividends from consolidated subsidiaries	12,376	39,174	27,990
Dividends paid	(5,077)	(4,309)	(4,184)
Net cash provided by (used in) financing activities	(3,077)	81,807	18,784
Net increase (decrease) in cash and cash equivalents	(2,861)	16,922	(42,608)
Cash and cash equivalents at beginning-of-period	21,031	4,109	46,717
Cash and cash equivalents at end-of-period	$ 18,170	$ 21,031	$ 4,109