Related Party Transactions (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
ABS [Member]
Related Party [Abstract]
Related party expenses	$ 1.5	$ 1.3	$ 1.6
UK Protection & Indemnity Association [Member]
Related Party [Abstract]
Related party expenses	3.6	3.4	3.2
Signal Member
Related Party [Abstract]
Related party expenses	0.7	0.5	0.6
Strasburger & Price, LLP Member
Related Party [Abstract]
Legal services	0.9	1.0	2.9
W. Sean O'Neil Attorney Member
Related Party [Abstract]
Legal services	0.1	$ 0.1	$ 0.1
Mansfield Service Partners Member
Related Party [Abstract]
Related party expenses	$ 29.4