Investments - Additional Information (Details)	3 Months Ended
Mar. 31, 2020 USD ($) Security	Dec. 31, 2019 USD ($) Security
Debt Securities, Available-for-sale [Line Items]
Available-for-sale Debt Securities	$ 32,393,000	$ 32,006,000
Number of securities in unrealized loss position \| Security	3	10
Proceeds from sale of investment in fixed maturity securities	$ 0.0
Proceeds from Sale of Other Investments	1,700,000
Gross realized gains and losses on sale of securities	0
Investments on deposit with the state insurance department	4,300,000
U.S. Treasury securities, obligations of U.S. Government agencies and Municipalities
Debt Securities, Available-for-sale [Line Items]
Available-for-sale Debt Securities	27,068,000	$ 26,622,000
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	9,100,000	4,600,000
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	7,500,000	7,700,000
Corporate Debt Securities
Debt Securities, Available-for-sale [Line Items]
Available-for-sale Debt Securities	$ 5,325,000	$ 5,384,000

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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 825
-Section 50
-Paragraph 1A
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-Publisher FASB
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