RESERVES FOR LOSSES AND LOSS SETTLEMENT EXPENSES (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Liability for Unpaid Claims and Claims Adjustment Expense [Roll Forward]
Gross liability for losses and loss settlement expenses at beginning of year	$ 969,437	$ 960,651	$ 971,911
Ceded losses and loss settlement expenses	(54,653)	(63,757)	(75,150)	$ (103,870)
Net liability for losses and loss settlement expenses at beginning of year	905,680	885,501	868,041
Losses and loss settlement expenses incurred for claims occurring during
Current year	560,482	566,555	494,841
Prior years	(40,395)	(56,744)	(57,487)
Total incurred	520,087	509,811	437,354
Losses and loss settlement expenses incurred for claims occurring during
Current year	225,022	247,651	203,868
Prior years	251,503	241,981	216,026
Total paid	476,525	489,632	419,894
Net liability for losses and loss settlement expenses at end of year	949,242	905,680	885,501
Ceded loss and loss settlement expenses	54,653	63,757	75,150
Gross liability for losses and loss settlement expenses at end of year	$ 1,003,895	$ 969,437	$ 960,651