Related Party Transactions (Details) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
ABS [Member]
Related Party [Abstract]
Related party expenses	$ 2,377,000	$ 1,774,000	$ 1,162,000
UK Protection & Indemnity Association [Member]
Related Party [Abstract]
Related party expenses	3,000,000
Signal [Member]
Related Party [Abstract]
Related party expenses	667,000	1,391,000
Strasburger & Price, LLP [Member]
Related Party [Abstract]
Legal services	$ 1,598,000	$ 1,278,000	$ 2,019,000