Condensed Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Revenues:
Net premiums written	$ 108,513	$ 92,399	$ 208,979	$ 174,656
Increase in unearned premiums	(7,802)	(14,038)	(13,865)	(21,257)
Net premiums earned	100,711	78,361	195,114	153,399
Net investment income	6,701	4,720	12,884	9,000
Realized investment gains, net	583	568	1,054	1,217
Other income	170	418	1,579	462
Total revenues	108,165	84,067	210,631	164,078
Losses and expenses:
Provision for losses and LAE	2,964	2,314	6,695	4,313
Other underwriting and operating expenses	31,409	27,148	62,797	54,646
Total losses and expenses	34,373	29,462	69,492	58,959
Income before income taxes	73,792	54,605	141,139	105,119
Income tax expense	21,534	17,412	40,930	33,088
Net income	$ 52,258	$ 37,193	$ 100,209	$ 72,031
Earnings per share:
Basic (in dollars per share)	$ 0.57	$ 0.41	$ 1.10	$ 0.80
Diluted (in dollars per share)	$ 0.57	$ 0.41	$ 1.09	$ 0.79
Weighted average shares outstanding:
Basic (in shares)	90,912	90,344	90,848	90,265
Diluted (in shares)	92,138	91,674	91,999	91,594
Net income	$ 52,258	$ 37,193	$ 100,209	$ 72,031
Other comprehensive income (loss):
Change in unrealized appreciation (depreciation) of investments, net of tax expense (benefit) of $5,049 and ($4,002) in the three months ended June 30, 2016 and 2015 and $10,763 and ($1,892) in the six months ended June 30, 2016 and 2015	10,702	(8,769)	24,061	(3,880)
Total other comprehensive income (loss)	10,702	(8,769)	24,061	(3,880)
Comprehensive income	$ 62,960	$ 28,424	$ 124,270	$ 68,151