Schedule I (Details) $ in Thousands	Dec. 31, 2020 USD ($)
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Cost	$ 172,606	[1],[2]
Market Value	210,723	[2]
Amount at which shown in the Balance Sheet	210,723	[2],[3]
Fixed maturity securities
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Cost	112,037
Market Value	117,713
Amount at which shown in the Balance Sheet	117,713	[3]
Government obligations
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Cost	24,026
Market Value	24,083
Amount at which shown in the Balance Sheet	24,083	[3]
General obligations of U.S. states, territories and political subdivisions
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Cost	17,186
Market Value	18,439
Amount at which shown in the Balance Sheet	18,439	[3]
Special revenue issuer obligations of U.S. states, territories and political subdivisions
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Cost	33,635
Market Value	36,134
Amount at which shown in the Balance Sheet	36,134	[3]
Public utilities
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Cost	11,509
Market Value	12,286
Amount at which shown in the Balance Sheet	12,286	[3]
Corporate debt securities
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Cost	25,681
Market Value	26,771
Amount at which shown in the Balance Sheet	26,771	[3]
Equity securities
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Cost	32,478
Market Value	64,919
Amount at which shown in the Balance Sheet	64,919	[3]
Public utilities
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Cost	323
Market Value	486
Amount at which shown in the Balance Sheet	486	[3]
Banks, trusts and insurance companies
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Cost	2,640
Market Value	5,938
Amount at which shown in the Balance Sheet	5,938	[3]
Industrial, miscellaneous and all other
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Cost	26,144
Market Value	46,802
Amount at which shown in the Balance Sheet	46,802	[3]
Technology
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Cost	3,371
Market Value	11,693
Amount at which shown in the Balance Sheet	11,693	[3]
Short-term investments
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Cost	15,170
Market Value	15,170
Amount at which shown in the Balance Sheet	15,170	[3]
Other investments
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Cost	12,921	[2]
Market Value	12,921	[2]
Amount at which shown in the Balance Sheet	12,921	[2],[3]
Total other investments
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Cost	28,091
Market Value	28,091
Amount at which shown in the Balance Sheet	$ 28,091	[3]

[1] Fixed maturity securities are shown at amortized cost and equity securities are shown at original cost.

[2] The above summary of investments does not include investments in related parties accounted for under the cost and equity methods of accounting in the amount of $2,572.

[3] All fixed maturity securities presented are classified as available-for-sale and shown at estimated fair value. Equity securities are shown at fair value.