Schedule I - Summary of Investments - Other than Investments in Related Parties (Details) $ in Thousands	Dec. 31, 2019 USD ($)
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Cost	$ 133,330
Fair value	129,071
Balance sheet value	129,071
Private Common Equity Securities
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Cost	1,000
Fair value	1,000
Balance sheet value	1,000
Private preferred equity securities
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Cost	3,000
Fair value	3,000
Balance sheet value	3,000
Equity Securities, Investment Summary [Member]
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Cost	4,000
Fair value	4,000
Balance sheet value	4,000
U.S. Treasury securities
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Cost	101,413
Fair value	101,186
Balance sheet value	101,186
Sovereign debt
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Cost	27,917
Fair value	23,885
Balance sheet value	23,885
Total debt securities
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Cost	129,330
Fair value	125,071
Balance sheet value	$ 125,071