Consolidated Statements of Earnings and Comprehensive Earnings - 10K (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Condensed Consolidated Statements of Earnings and Comprehensive Earnings
Net premiums earned	$ 687,375	$ 630,802	$ 576,571
Net investment income	55,608	52,763	58,831
Net realized investment gains	32,182	22,036	26,528
Other-than-temporary-impairment losses on investments			(1,156)
Consolidated revenue	775,165	705,601	660,774
Losses and settlement expenses	296,609	259,801	271,645
Policy acquisition costs	229,283	210,651	196,362
Insurance operating expenses	54,464	53,557	44,971
Interest expense on debt	7,438	8,095	6,050
General corporate expenses	10,222	8,746	7,867
Total expenses	598,016	540,850	526,895
Equity in earnings of unconsolidated investees	12,338	10,915	8,853
Earnings before income taxes	189,487	175,666	142,732
Income tax expense:
Current	48,596	43,346	35,605
Deferred	5,446	6,065	3,781
Income tax expense:	54,042	49,411	39,386
Net earnings	135,445	126,255	103,346
Other comprehensive earnings (loss), net of tax	35,356	(7,143)	25,845
Comprehensive earnings	$ 170,801	$ 119,112	$ 129,191
Basic:
Net earnings per share (in dollars per share)	$ 3.15	$ 2.95	$ 2.44
Comprehensive earnings per share (in dollars per share)	$ 3.97	$ 2.79	$ 3.04
Diluted:
Net earnings per share (in dollars per share)	$ 3.09	$ 2.90	$ 2.39
Comprehensive earnings per share (in dollars per share)	$ 3.90	$ 2.74	$ 2.99
Weighted average number of common shares outstanding
Basic (in shares)	43,020	42,744	42,431
Diluted (in shares)	43,819	43,514	43,160