Schedule VI. Supplemental Information Concerning Property and Casualty Insurance Operations (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Supplemental Information for Property, Casualty Insurance Underwriters [Line Items]
Net Realized Investment Gains	$ 2,846	$ 7,270	$ 8,695
Claims and Claim Adjustment Expenses Incurred Related to: Current Year	560,482	566,555	494,841
Claims and Claim Adjustment Expenses Incurred Related to: Prior Years	(40,395)	(56,744)	(57,487)
Consolidated Property and Casualty Insurance Entity [Member]
Supplemental Information for Property, Casualty Insurance Underwriters [Line Items]
Deferred Policy Acquisition Costs	90,547	72,861	67,663
Reserves for Unpaid Claims and Claim Adjustment Expenses	1,003,895	969,437	960,651
Unearned Premiums	414,971	378,635	340,387
Earned Premiums	851,695	766,939	694,192
Net Realized Investment Gains	1,124	4,177	6,260
Net Investment Income	46,559	44,236	46,332
Claims and Claim Adjustment Expenses Incurred Related to: Current Year	560,482	566,555	494,841
Claims and Claim Adjustment Expenses Incurred Related to: Prior Years	(40,395)	(56,744)	(57,487)
Amortization of Deferred Policy Acquisition Costs	180,183	161,310	147,175
Paid Claims and Claim Adjustment Expenses	476,525	489,631	419,894
Premiums Written	$ 887,874	$ 804,715	$ 722,821