CONSOLIDATED STATEMENTS OF INCOME - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
REVENUES
Premiums earned (affiliated $603,233, $586,609 and $566,103)	$ 607,158	$ 592,408	$ 570,266
Net investment income	45,479	47,490	45,582
Net realized investment gains, excluding impairment losses on securities available-for-sale	7,644	5,338	7,634
Total other-than-temporary impairment losses on securities available-for-sale	(1,088)	(1,264)	(1,481)
Portion of other-than-temporary impairment losses on fixed maturity securities available-for-sale reclassified from other comprehensive income (before taxes)	0	0	0
Net impairment losses on securities available-for-sale	(1,088)	(1,264)	(1,481)
Net realized investment gains	6,556	4,074	6,153
Other income (loss) (affiliated $143, $1,021 and $1,214)	(348)	1,011	1,725
Total revenues	658,845	644,983	623,726
LOSSES AND EXPENSES
Losses and settlement expenses (affiliated $417,259, $385,708 and $368,722)	421,969	386,897	370,736
Dividends to policyholders (all affiliated)	7,610	13,800	7,705
Amortization of deferred policy acquisition costs (affiliated $107,854, $106,931 and $101,090)	108,910	108,403	102,184
Other underwriting expenses (affiliated $76,932, $69,560 and $68,305)	76,806	69,612	68,418
Interest expense (all affiliated)	337	337	337
Other expenses (affiliated $1,825, $1,860 and $1,822)	3,397	2,727	2,690
Total losses and expenses	619,029	581,776	552,070
Income before income tax expense	39,816	63,207	71,656
INCOME TAX EXPENSE (BENEFIT)
Current	8,004	18,061	18,611
Deferred	(7,426)	(1,057)	2,883
Total income tax expense	578	17,004	21,494
Net income	$ 39,238	$ 46,203	$ 50,162
Net income per common share - basic and diluted	$ 1.84	$ 2.20	$ 2.43
Average number of common shares outstanding - basic and diluted (in shares)	21,326,358	21,006,302	20,621,919