CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Millions	Jun. 30, 2021	Dec. 31, 2020
Investments
Amortized Cost of Fixed Maturity Securities	$ 36,910.7	$ 36,546.5
Debt Securities, Available-for-sale, Allowance for credit losses for Fixed Maturity Securities	0.0	6.8
Other Assets [Abstract]
Accounts Receivable, after Allowance for Credit Loss	31.0	38.8
Reinsurance Recoverable, Allowance for Credit Loss	$ 12.4	$ 11.7
Stockholders' Equity
Common Stock, Par Value (in dollars per share)	$ 0.10	$ 0.10
Common Stock, Shares Authorized	725,000,000	725,000,000
Common Stock, Shares Issued	307,226,327	306,566,572
Treasury Stock, Shares at Cost	102,876,514	102,876,514
Income Taxes Receivable	$ 0.0	$ 72.7

Amount, after allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business.

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