ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) (Details 2) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Tax benefit (expense)	$ (5,764)	$ (10,280)
Net of tax	15,396
Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Prior service credits	(371)	280
Actuarial losses	155	(61)
Total before tax	(216)	219
Tax benefit (expense)	79	(81)
Net of tax	$ (137)	$ 138