CONSOLIDATED BALANCE SHEETS (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
Fixed maturities, available-for-sale, amortized cost	$ 1,816,710	$ 1,855,598
Equity securities, available-for-sale, cost	$ 73,567	$ 64,793
Preferred stock, par value	$ 0.10	$ 0.10
Preferred stock, authorized shares	1,000,000	1,000,000
Preferred stock, issued shares	0	0
Common stock, par value	$ 0.10	$ 0.10
Common stock, authorized shares	50,000,000	50,000,000
Common stock, issued shares	17,467,615	17,274,440
Treasury stock, shares	3,511,380	1,532,273