SCHEDULE VI-SUPPLEMENTARY INFORMATION CONCERNING PROPERTY-CASUALTY INSURANCE OPERATIONS (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Claims and claim adjustment expenses incurred related to:
Current accident year	$ 364,472	$ 361,451	$ 332,282
Prior accident years	(65,427)	(64,842)	(72,481)
Amortization of deferred acquisition costs	241,078	229,283	210,651
Consolidated property-casualty insurance operations
SUPPLEMENTARY INFORMATION CONCERNING PROPERTY-CASUALTY INSURANCE OPERATIONS
Deferred policy acquisition costs	69,829	65,123	61,508
Claims and claim adjustment expense reserves	1,103,785	1,121,040	1,129,433
Unearned premiums, gross	422,094	401,412	392,081
Net premiums earned	700,161	687,375	630,802
Net investment income	54,644	55,608	52,763
Claims and claim adjustment expenses incurred related to:
Current accident year	364,472	361,451	332,282
Prior accident years	(65,427)	(64,842)	(72,481)
Amortization of deferred acquisition costs	241,078	229,283	210,651
Paid claims and claims adjustment expenses	279,038	285,184	283,891
Net premiums written	$ 721,971	$ 703,152	$ 666,322