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 expense 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), for which no credit loss was previously recorded.

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Amount of increase (decrease) in allowance for credit loss 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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-Publisher FASB
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-Topic 326
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Amount of decrease in 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) from sale.

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Investments- Allowance for Credit Loss Impairments on Fixed Maturity Securities (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Jun. 30, 2021	Dec. 31, 2020	Jun. 30, 2020	Dec. 31, 2019
Debt Securities, Available-for-sale, Allowance for Credit Loss
Available-for-sale allowance for credit loss not previously recorded			$ 7.7
Fixed maturity securities
Debt Securities, Available-for-sale, Allowance for Credit Loss
Beginning balance	$ 7.7	$ 0.0	7.7	$ 0.0	$ 1.1	$ 0.0	$ 0.0	$ 0.0
Available-for-sale allowance for credit loss not previously recorded	6.6	0.0	7.7	0.0
Net (increases) decreases related to credit losses previously reported	0.0	0.0	0.0	0.0
Reduction of credit allowances related to sales	0.0	0.0	0.0	0.0
Write-offs	0.0	0.0	0.0	0.0
Ending balance	$ 7.7	$ 0.0	$ 7.7	$ 0.0