Investments - Additional Information (Details) $ in Thousands	12 Months Ended
Dec. 31, 2020 USD ($) Security	Dec. 31, 2019 USD ($) Security	Dec. 31, 2018 USD ($)
Debt Securities, Available-for-sale [Line Items]
Available-for-sale Debt Securities	$ 36,254	$ 32,006
Number of securities in unrealized loss position \| Security	3	10
Proceeds from sale of investment in fixed maturity securities	$ 8,600	$ 5,800
Proceeds from Sale of Other Investments	11,000	8,500
Payments to Acquire Investments	14,168	17,520	$ 9,284
Investments on deposit with the state insurance department	4,200
U.S. Treasury securities, obligations of U.S. Government agencies and Municipalities
Debt Securities, Available-for-sale [Line Items]
Available-for-sale Debt Securities	28,831	26,622
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	11,300
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	7,000
Corporate Debt Securities
Debt Securities, Available-for-sale [Line Items]
Available-for-sale Debt Securities	$ 7,423	$ 5,384

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

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