Other Operating Expenses and Other Expenses (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Other Operating Expenses and Other Expenses [Abstract]
Amortization of policy acquisition costs	$ 16,660	$ 21,258	$ 62,406	$ 63,029
Other underwriting expenses of the operating segments	13,759	13,132	47,280	46,617
Other operating expenses of the Corporate and Other segment	7,805	7,302	23,556	22,641
Total	38,224	41,692	133,242	132,287
Other expenses	$ 60	$ 372	$ 1,792	$ 1,055