CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Investments
Amortized Cost of Fixed Maturity Securities	$ 41,239.4	$ 41,079.3
Debt Securities, Available-for-sale, Allowance for credit losses for Fixed Maturity Securities	12.5	0.0
Allowance for credit losses for Mortgage Loans	14.6	0.0
Other Assets [Abstract]
Accounts Receivable, after Allowance for Credit Loss	41.1	10.3
Reinsurance Recoverable, Allowance for Credit Loss	$ 1.8	$ 0.0
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	306,465,302	305,813,326
Treasury Stock, Shares at Cost	102,876,514	102,876,514

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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