Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Fixed maturities, available-for-sale, amortized cost	$ 2,034,765	$ 1,816,710
Equity securities, available-for-sale, cost	$ 85,004	$ 73,567
Preferred stock, par value	$ 0.10	$ 0.10
Preferred stock, authorized shares	1,000,000	1,000,000
Preferred stock, issued shares
Common stock, par value	$ 0.10	$ 0.10
Common stock, authorized shares	50,000,000	50,000,000
Common stock, issued shares	17,558,046	17,467,615
Treasury stock, shares	3,511,380	3,511,380