Investments - Additional Information (Details) $ in Millions	9 Months Ended
Sep. 30, 2022 USD ($) Security	Dec. 31, 2021 USD ($) Security
Debt Securities, Available-for-sale [Line Items]
Available-for-sale Debt Securities	$ 29.7	$ 38.3
Available-for-sale Debt Securities	$ 5.7	$ 7.4
Number of securities in unrealized loss position \| Security	42	23
Proceeds from sale of investment in fixed maturity securities and maturing time deposits	$ 7.3
Losses realized on the sale of securities	0.1
Investments on deposit with the state insurance department	4.0
U.S. Treasury securities, obligations of U.S. Government agencies and municipalities
Debt Securities, Available-for-sale [Line Items]
Available-for-sale Debt Securities	21.0	$ 30.0
Corporate Debt Securities
Debt Securities, Available-for-sale [Line Items]
Available-for-sale Debt Securities	7.8	8.3
Bank Time Deposits
Debt Securities, Available-for-sale [Line Items]
Available-for-sale Debt Securities	$ 5.5	$ 5.5

Carrying amount of cash and investment securities on deposit with state regulatory authorities in connection with capital requirements.

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