CONDENSED CONSOLIDATED STATEMENTS OF INCOME (unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
PREMIUMS EARNED AND OTHER REVENUES
Direct premiums written	$ 357,960	$ 342,781	$ 647,194	$ 612,765
Change in unearned premium	(54,852)	(68,754)	(48,709)	(76,477)
Direct premium earned	303,108	274,027	598,485	536,288
Ceded premium earned	(92,751)	(81,755)	(178,401)	(161,439)
Premiums earned, net	210,357	192,272	420,084	374,849
Net investment income	7,410	5,786	15,552	10,571
Net realized gains (losses) on investments	(1,605)	145	(13,130)	(2,496)
Net change in unrealized gains (losses) of equity securities	3,759	(1,521)	21,791	(6,630)
Commission revenue	6,048	5,709	11,553	10,980
Policy fees	5,997	5,764	11,018	10,539
Other revenue	1,756	1,633	3,440	3,475
Total premiums earned and other revenues	233,722	209,788	470,308	401,288
OPERATING COSTS AND EXPENSES
Losses and loss adjustment expenses	113,296	89,842	226,390	165,768
General and administrative expenses	69,496	58,698	139,244	122,573
Total operating costs and expenses	182,792	148,540	365,634	288,341
INCOME BEFORE INCOME TAXES	50,930	61,248	104,674	112,947
Income tax expense	13,637	15,164	27,233	26,808
NET INCOME	$ 37,293	$ 46,084	$ 77,441	$ 86,139
Basic earnings per common share (in dollars per share)	$ 1.09	$ 1.32	$ 2.24	$ 2.47
Weighted average common shares outstanding - Basic (in shares)	34,311	34,909	34,525	34,874
Diluted earnings per common share (in dollars per share)	$ 1.08	$ 1.29	$ 2.22	$ 2.42
Weighted average common shares outstanding - Diluted (in shares)	34,612	35,589	34,903	35,636
Cash dividend declared per common share (in dollars per share)	$ 0.16	$ 0.14	$ 0.32	$ 0.28