QUARTERLY RESULTS OF OPERATIONS - (Summary of Unaudited Quarterly Results of Operations) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Quarterly Financial Information Disclosure [Abstract]
Net premiums earned	$ 95,188	$ 87,374	$ 92,306	$ 88,784	$ 91,098	$ 98,493	$ 83,557	$ 82,109	$ 363,652	$ 355,257	$ 333,481
Total Revenue	108,987	99,476	105,301	101,197	96,442	110,832	95,742	93,077	414,961	396,093	391,662
Losses and loss adjustment expenses	78,796	62,105	65,340	66,839	72,318	62,457	47,570	46,071	273,080	228,416	247,557
Total costs and expenses	118,118	94,099	95,596	106,435	108,836	99,862	83,726	83,461	414,248	375,885	382,735
Net (loss) income attributable to Federated National Holding Company shareholders	$ (6,893)	$ 4,659	$ 7,110	$ (3,865)	$ (9,305)	$ 7,950	$ 8,820	$ 7,463	$ 1,011	$ 14,928	$ 7,989
Net income (loss) per share - basic (in dollars per share)	$ (0.51)	$ 0.36	$ 0.55	$ (0.30)	$ (0.73)	$ 0.62	$ 0.69	$ 0.58	$ 0.08	$ 1.17	$ 0.61