OTHER COMPREHENSIVE INCOME (Amounts Reclassified from Accumulated Other Comprehensive Income to Earnings) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Interest expense	$ (38,455)	$ (33,333)	$ (72,531)	$ (67,065)
Cost of revenues	738,988	664,641	1,366,337	1,254,649
Selling, administrative and general expenses	82,793	82,681	164,914	159,149
Benefit from income taxes	45,652	53,241	42,477	41,772
Total	120,139	124,709	165,060	164,866
Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Total	755	321	1,502	635
Reclassification Adjustment for Cash Flow Hedge Losses [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Interest expense	539	497	1,067	983
Benefit from income taxes	(211)	(196)	(420)	(388)
Total	328	301	647	595
Amortization of Pension and Postretirement Plan Actuarial Loss and Prior Service Cost [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Cost of revenues	575	27	1,145	55
Selling, administrative and general expenses	128	6	261	12
Benefit from income taxes	(276)	(13)	(551)	(27)
Total	$ 427	$ 20	$ 855	$ 40