Investments - Schedule of Carrying Amounts and Fair Values of Available for Sale Securities (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Fixed maturity securities available for sale:
Cost Basis	$ 19.9	$ 19.6
Unrealized Gains	6.4	0.7
Unrealized Losses	(0.2)	(1.1)
Fair Value	26.1	19.2
Corporate debt securities
Fixed maturity securities available for sale:
Cost Basis	19.9	19.6
Unrealized Gains	6.4	0.7
Unrealized Losses	(0.2)	(1.1)
Fair Value	26.1	19.2
Carrying Value
Fixed maturity securities available for sale:
Fair Value	26.1	19.2
Carrying Value \| Corporate debt securities
Fixed maturity securities available for sale:
Fair Value	$ 26.1	$ 19.2

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) 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, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) 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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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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