Condensed Consolidated Balance Sheets (Parenthetical) (USD $) In Millions, except Share data, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Amortized Cost of Fixed Maturity Securities	$ 4,317.2	$ 4,341.7
Equity Securities at Cost	555.5	561.5
Fair Value of Notes Payable	$ 804.1us-gaap_NotesPayableFairValueDisclosure	$ 804.4us-gaap_NotesPayableFairValueDisclosure
Common Stock, Par Value	$ 0.1	$ 0.1
Common Stock, Shares Authorized	100,000,000us-gaap_CommonStockSharesAuthorized	100,000,000us-gaap_CommonStockSharesAuthorized
Common Stock, Shares Issued	51,826,395us-gaap_CommonStockSharesIssued	52,418,246us-gaap_CommonStockSharesIssued
Common Stock, Shares, Outstanding	51,826,395us-gaap_CommonStockSharesOutstanding	52,418,246us-gaap_CommonStockSharesOutstanding

This item represents the cost of debt securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

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Fair value portion of notes payable.

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