Segment Information (Details) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020 USD ($)	Sep. 30, 2020 USD ($)	Jun. 30, 2020 USD ($)	Mar. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Sep. 30, 2019 USD ($)	Jun. 30, 2019 USD ($)	Mar. 31, 2019 USD ($)	Dec. 31, 2020 USD ($) Segment	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Segment Information [Abstract]
Number of reportable segments | Segment									1
Revenues [Abstract]
Net premiums earned	$ 120,273	$ 117,853	$ 97,730	$ 109,659	$ 111,357	$ 110,288	$ 115,631	$ 110,012	$ 445,515	$ 447,288	$ 432,880
Net investment income	6,321	5,486	6,379	7,236	6,815	6,703	6,500	6,231	25,422	26,249	22,048
Net realized and unrealized gains (losses) on investments	$ 7,761	$ 144	$ 10,615	$ (27,756)	$ 3,848	$ 125	$ 2,889	$ 6,027	(9,236)	12,889	(25,691)
Commissions and other income									7,048	9,171	9,932
Total revenues									468,749	495,597	439,169
Property and Casualty Insurance [Member]
Revenues [Abstract]
Net premiums earned									445,515	447,288	432,880
Net investment income									25,422	26,249	22,048
Net realized and unrealized gains (losses) on investments									(9,236)	12,889	(25,691)
Commissions and other income									7,048	9,171	9,932
Total revenues									$ 468,749	$ 495,597	$ 439,169