Consolidated Statements of Financial Position (Unaudited) (Parenthetical) (USD $) In Thousands, except Share data	Jun. 30, 2011	Dec. 31, 2010
Investments:
Fixed maturities available-for-sale, cost	$ 574,094	$ 578,412
Fixed maturities held-to-maturity, fair value	108,608	79,103
Equity securities available-for-sale, cost	20,551	19,844
Real estate held for investment, accumulated depreciation	1,082	1,017
Due premiums, allowance for doubtful accounts	$ 1,489	$ 1,568
Common Class A [Member]
Stockholders' equity:
Common stock, shares authorized (in shares)	100,000,000	100,000,000
Common stock, shares issued (in shares)	51,825,079	51,822,497
Common stock, shares in treasury (in shares)	3,135,738	3,135,738
Common Class B [Member]
Stockholders' equity:
Common stock, shares authorized (in shares)	2,000,000	2,000,000
Common stock, shares issued (in shares)	1,001,714	1,001,714
Common stock, shares outstanding (in shares)	1,001,714	1,001,714