Investments - Additional Information (Details) $ in Thousands	9 Months Ended
Sep. 30, 2019 USD ($) Security	Dec. 31, 2018 USD ($) Security
Debt Securities, Available-for-sale [Line Items]
Available-for-sale Debt Securities	$ 30,382	$ 22,137
Number of securities in unrealized loss position \| Security	8	20
Proceeds from sale of investment in fixed maturity securities	$ 5,800
Proceeds from Sale of Other Investments	8,400
Investments on deposit with the state insurance department	4,800
U.S. Treasury securities, obligations of U.S. Government agencies and Municipalities
Debt Securities, Available-for-sale [Line Items]
Available-for-sale Debt Securities	25,000	$ 21,514
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	2,200	4,800
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	7,700	8,100
Corporate Debt Securities
Debt Securities, Available-for-sale [Line Items]
Available-for-sale Debt Securities	$ 5,382	$ 623

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

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