Schedule IV - Reinsurance (Details) - USD ($) $ in Thousands		3 Months Ended								12 Months Ended
		Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Schedule IV - Reinsurance [Abstract]
Direct premiums										$ 557,795	$ 570,959	$ 562,364
Ceded to other companies	[1]									113,125	124,446	131,080
Assumed from other companies										845	775	1,596
Net		$ 120,273	$ 117,853	$ 97,730	$ 109,659	$ 111,357	$ 110,288	$ 115,631	$ 110,012	$ 445,515	$ 447,288	$ 432,880
% of amount assumed to net										0.20%	0.20%	0.40%
Retrocessions associated with premiums assumed from other companies										$ 0	$ 0	$ 0

[1] Included in Ceded to Other Companies is $0 for each of 2020, 2019 and 2018 relating to retrocessions associated with premiums assumed from other companies.  Percentage of Amount Assumed to Net above considers the impact of this retrocession.