Consolidated Statements of Income (Unaudited) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Revenues
Net premiums earned	$ 176,817	$ 161,503
Investment income, net of investment expenses	26,464	29,146
Net realized investment gains
Other-than-temporary impairment charges	0	0
All other net realized gains (includes reclassifications for net unrealized gains on available-for-sale securities of $1,909 in 2013; and $2,794 in 2012; previously included in accumulated other comprehensive income)	1,909	2,794
Total net realized investment gains	1,909	2,794
Other income	115	256
Total revenues	205,305	193,699
Benefits, Losses and Expenses
Losses and loss settlement expenses	97,470	91,484
Future policy benefits	8,236	10,138
Amortization of deferred policy acquisition costs	38,081	34,551
Other underwriting expenses (includes reclassifications for employee benefit costs of $1,242 in 2013; and $643 in 2012; previously included in accumulated other comprehensive income)	22,348	21,994
Interest on policyholders’ accounts	9,320	10,656
Total benefits, losses and expenses	175,455	168,823
Income before income taxes	29,850	24,876
Federal income tax expense (includes reclassifications of $234 in 2013; and $752 in 2012; previously included in accumulated other comprehensive income)	7,457	5,692
Net income	22,393	19,184
Other comprehensive income
Change in net unrealized appreciation on investments	15,161	13,603
Change in liability for underfunded employee benefit plans	0	0
Other comprehensive income, before tax and reclassification adjustments	15,161	13,603
Income tax effect	(5,306)	(4,761)
Other comprehensive income, after tax, before reclassification adjustments	9,855	8,842
Reclassification adjustment for net realized gains included in income	(1,909)	(2,794)
Reclassification adjustment for employee benefit costs included in expense	1,242	643
Total reclassification adjustments, before tax	(667)	(2,151)
Income tax effect	234	752
Total reclassification adjustments, after tax	(433)	(1,399)
Comprehensive income	$ 31,815	$ 26,627
Weighted average common shares outstanding (in shares)	25,245,497	25,505,962
Basic earnings per common share (in dollars per share)	$ 0.89	$ 0.75
Diluted earnings per common share (in dollars per share)	$ 0.88	$ 0.75
Cash dividends declared per common share (in dollars per share)	$ 0.15	$ 0.15