CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Millions	Jun. 30, 2020	Dec. 31, 2019
Investments
Debt Securities, Available-for-sale, Allowance for credit losses for Fixed Maturity Securities	$ 29.8	$ 0.0
Amortized Cost of Fixed Maturity Securities	40,840.4	41,079.3
Allowance for credit losses for Mortgage Loans	13.2	0.0
Other Assets [Abstract]
Accounts Receivable, after Allowance for Credit Loss	47.5	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	306,361,248	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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The reserve to cover probable credit losses related to specifically identified fixed maturity real estate loans as well as probable credit losses inherent in the remainder of that loan portfolio.

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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of allowance for credit loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of allowance for credit loss on reinsurance recoverable.

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Number of common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends.

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