Condensed Consolidated Balance Sheets (Parenthetical) (USD $)	Jun. 30, 2011	Dec. 31, 2010
Amortized Cost of Fixed Maturity Securities	$ 4,281,800,000	$ 4,240,800,000.0
Equity Securities at Cost	434,800,000	449,200,000.0
Fair Value of Automobile Loan Receivables	232,800,000	340,000,000.0
Fair Value of Certificates of Deposits	0	336,600,000.0
Fair Value of Notes Payable	$ 653,500,000	$ 628,000,000.0
Common Stock, Par Value	$ 0.10	$ 0.1
Common Stock, Shares Authorized	100,000,000	100,000,000
Common Stock, Shares Issued	60,459,691	61,066,587
Common Stock, Shares Outstanding	60,459,691	61,066,587