Consolidated Statements Of Operations (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 earned	$ 779,321	$ 731,546	$ 1,546,406	$ 1,452,283
Net investment income	31,414	31,697	61,069	63,203
Net realized investment gains (losses)	45,381	(39,348)	70,438	(49,309)
Other	1,887	2,276	4,010	4,542
Total revenues	858,003	726,171	1,681,923	1,470,719
Expenses:
Losses and loss adjustment expenses	595,086	521,214	1,189,168	1,035,614
Policy acquisition costs	139,922	135,140	281,482	268,987
Other operating expenses	57,700	64,537	118,994	130,229
Interest	960	769	1,910	1,519
Total expenses	793,668	721,660	1,591,554	1,436,349
Income before income taxes	64,335	4,511	90,369	34,370
Income tax expense (benefit)	15,462	(5,128)	18,173	(1,434)
Net income	$ 48,873	$ 9,639	$ 72,196	$ 35,804
Net income per share:
Basic (in dollars per share)	$ 0.88	$ 0.17	$ 1.31	$ 0.65
Diluted (in dollars per share)	$ 0.88	$ 0.17	$ 1.31	$ 0.65
Weighted average shares outstanding:
Basic (in shares)	55,254	55,160	55,227	55,149
Diluted (in shares)	55,322	55,179	55,294	55,169
Dividends paid per share (in dollars per share)	$ 0.62000	$ 0.6175	$ 1.24	$ 1.235