Schedule VI - Supplemental Information Concerning Property-Casualty Insurance Operations (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Supplemental Information For Property, Casualty Insurance Underwriters [Abstract]
Deferred Policy Acquisition Costs	$ 14,291	$ 16,002
Reserves for Unpaid Claims and Claim Adjustment Expenses	527,247	527,100
Unearned Premiums	298,061	276,642
Earned Premiums	363,087	361,037
Net Investment Income	18,232	18,874
Current year	250,075	248,203
Prior years	5,953	40,105
Amortization of Deferred Policy Acquisition Costs	37,436	34,265
Paid Claims and Claims Adjustment Expenses	322,985	274,150
Premiums Written	$ 363,798	$ 365,583