Consolidated Balance Sheets Consolidated Balance Sheets (Parenthetical) (USD $) In Millions, except Share data, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Amortized Cost of Fixed Maturity Securities	$ 4,283.8	$ 4,266.1
Equity Securities at Cost	462.7	367.3
Fair Value of Notes Payable	$ 675.5	$ 638.7
Common Stock, Par Value	$ 0.1	$ 0.1
Common Stock, Shares Authorized	100,000,000	100,000,000
Common Stock, Shares Issued	58,454,390	60,248,582
Common Stock, Shares Outstanding	58,454,390	60,248,582