Condensed Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Investments:
Fixed maturity securities-held-to-maturity, at amortized cost (fair value $711,264 and $664,371 in 2015 and 2014, respectively)	$ 686,618	$ 639,631
Fixed maturity securities-available-for-sale, at fair value (cost $357,319 and $327,004 in 2015 and 2014, respectively)	362,804	331,242
Equity securities-available-for-sale, at fair value (cost $0 in 2015 and 2014)	28	28
Short-term investments	12,184	33,684
Other investments	11,729	11,748
Total investments	1,073,363	1,016,333
Cash and cash equivalents	79,731	90,956
Amounts recoverable from reinsurers	87,377	85,888
Premiums receivable, net of allowance	188,281	178,917
Deferred income taxes	30,826	31,231
Accrued interest receivable	12,042	11,637
Property and equipment, net	7,180	7,240
Deferred policy acquisition costs	20,791	19,649
Federal income tax recoverable		1,082
Other assets	15,386	14,287
Total assets	1,514,977	1,457,220
Liabilities:
Reserves for loss and loss adjustment expenses	704,938	687,602
Unearned premiums	172,042	168,576
Reinsurance premiums payable	1,862	843
Amounts held for others	43,298	42,827
Policyholder deposits	47,833	48,722
Insurance-related assessments	30,288	29,315
Accounts payable and other liabilities	32,255	30,110
Payable for investments purchased	20,808	2,257
Total liabilities	1,053,324	1,010,252
Shareholders' equity:
Voting-$0.01 par value authorized shares-50,000,000 in 2015 and 2014; 20,236,943 and 20,155,936 shares issued and 18,978,693 and 18,897,686 shares outstanding in 2015 and 2014, respectively	202	201
Additional paid-in capital	200,714	199,138
Treasury stock at cost (1,258,250 shares in 2015 and 2014)	(22,370)	(22,370)
Accumulated earnings	279,479	267,189
Accumulated other comprehensive income, net	3,628	2,810
Total shareholders' equity	461,653	446,968
Total liabilities and shareholders' equity	$ 1,514,977	$ 1,457,220