Investments - Additional Information (Details) $ in Millions	6 Months Ended
Jun. 30, 2022 USD ($) Security	Dec. 31, 2021 USD ($) Security
Debt Securities, Available-for-sale [Line Items]
Available-for-sale Debt Securities	$ 33.0	$ 38.3
Number of securities in unrealized loss position \| Security	34	23
Proceeds from sale of investment in fixed maturity securities and maturing time deposits	$ 3.6
Investments on deposit with the state insurance department	4.1
U.S. Treasury securities, obligations of U.S. Government agencies and municipalities
Debt Securities, Available-for-sale [Line Items]
Available-for-sale Debt Securities	25.1	$ 30.0
U.S. Treasury securities, obligations of U.S. Government agencies and municipalities \| Short-term Investments
Debt Securities, Available-for-sale [Line Items]
Available-for-sale Debt Securities	9.3	7.4
U.S. Treasury securities, obligations of U.S. Government agencies and municipalities \| Bank Time Deposits
Debt Securities, Available-for-sale [Line Items]
Available-for-sale Debt Securities	5.6	5.5
Corporate Debt Securities
Debt Securities, Available-for-sale [Line Items]
Available-for-sale Debt Securities	$ 7.9	$ 8.3

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

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