ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) (Details 2) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Tax (expense) benefit	$ (10,421)	$ (10,136)
Net of tax	17,270
Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Prior service credits	280	72
Actuarial losses	(61)	(2,258)
Total before tax	219	(2,186)
Tax (expense) benefit	(81)	804
Net of tax	$ 138	$ (1,382)