Investments - Net Investment Income (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Net Investment Income [Line Items]
Net investment income	$ 8.4	$ 1.9	$ 1.5
Gross investment income	8.8	2.0	1.5
Investment expense	0.4	0.1	0.0
Interest on cash and cash equivalents
Net Investment Income [Line Items]
Net investment income	1.2	0.4	1.0
Fixed maturities
Net Investment Income [Line Items]
Net investment income	5.7	1.5	0.1
Short-term investments
Net Investment Income [Line Items]
Net investment income	$ 1.9	$ 0.1	$ 0.4

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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Amount of expenses related to the generation of investment income.

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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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