Investments - Additional Information (Details) $ in Millions	9 Months Ended
Sep. 30, 2023 USD ($) Security	Dec. 31, 2022 USD ($) Security
Debt Securities, Available-for-sale [Line Items]
Available-for-sale Debt Securities	$ 29.3	$ 28.8
Available-for-sale Debt Securities	7.5	$ 6.4
Equity investment in a non-consolidated subsidiary	$ 2.5
Number of securities in unrealized loss position \| Security	35	33
Proceeds from sale of investment in fixed maturity securities and maturing time deposits	$ 6.1
Payments to acquire investments	6.2
Investments on deposit with the state insurance department	4.2
U.S. Treasury securities, obligations of U.S. Government agencies and municipalities
Debt Securities, Available-for-sale [Line Items]
Available-for-sale Debt Securities	24.5	$ 21.0
Corporate Debt Securities
Debt Securities, Available-for-sale [Line Items]
Available-for-sale Debt Securities	4.8	7.8
Bank Time Deposits
Debt Securities, Available-for-sale [Line Items]
Available-for-sale Debt Securities	$ 5.7	$ 5.6

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

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