Investments - Net Investment Income (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Net Investment Income [Line Items]
Gross investment income	$ 1.3	$ 0.2	$ 2.3	$ 0.4
Investment expense	0.1	0.0	0.2	0.0
Net investment income	1.2	0.2	2.1	0.4
Interest on cash and cash equivalents
Net Investment Income [Line Items]
Net investment income	0.1	0.1	0.1	0.3
Fixed maturities
Net Investment Income [Line Items]
Net investment income	1.1	0.1	2.0	0.1
Short-term investments
Net Investment Income [Line Items]
Net investment income	$ 0.1	$ 0.0	$ 0.2	$ 0.0

Amount, before investment expense, of income earned from investments in securities and real estate. Includes, but is not limited to, real estate investment, policy loans, dividends, and interest. Excludes realized gain (loss) on investments.

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-SubTopic 220
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Amount of expenses related to the generation of investment income.

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-Publisher FASB
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Amount, after investment expense, of income earned from investments in securities and real estate. Includes, but is not limited to, real estate investment, policy loans, dividends, and interest. Excludes realized gain (loss) on investments.

+ References

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