Investments - Net Realized Gains on Sales of Investments (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Net Investment Income [Line Items]
Gain (Loss) on Hedging Activity	$ (0.3)	$ 0.0	$ 0.0	$ 0.0
Fixed Maturities
Net Investment Income [Line Items]
Gains on Sales	14.2	10.3	28.0	42.7
Losses on Sales	(23.9)	(0.4)	(27.5)	(1.7)
Derivative
Net Investment Income [Line Items]
Gain (Loss) on Hedging Activity	$ (0.3)	$ 0.0	$ 0.0	$ 0.0

Amount of realized gain 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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-Publisher FASB
-Name Accounting Standards Codification
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