ACCUMULATED OTHER COMPREHENSIVE INCOME/(LOSS) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Jan. 02, 2016
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax
Balance	$ 615,088
Other comprehensive income/(loss), net of tax	20,141	$ (8,469)	$ (54,320)
Balance	702,621	615,088
Tax (benefit)/expense	500	500	2,500
Foreign Currency Translation Adjustments
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax
Balance	(118,400)	(110,100)	(51,800)
Other comprehensive income/(loss) before reclassifications	18,700	(8,300)	(58,300)
Amounts reclassified from accumulated other comprehensive income/(loss)	0	0	0
Other comprehensive income/(loss), net of tax	18,700	(8,300)	(58,300)
Balance	(99,700)	(118,400)	(110,100)
Pension and Post-Retirement Plan Benefit Adjustments
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax
Balance	(51,500)	(51,500)	(56,100)
Other comprehensive income/(loss) before reclassifications	0	0	0
Amounts reclassified from accumulated other comprehensive income/(loss)	2,200	0	4,600
Other comprehensive income/(loss), net of tax	2,200	0	4,600
Balance	(49,300)	(51,500)	(51,500)
AOCI Including Portion Attributable to Noncontrolling Interest
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax
Balance	(169,900)	(161,600)	(107,900)
Other comprehensive income/(loss) before reclassifications	18,700	(8,300)	(58,300)
Amounts reclassified from accumulated other comprehensive income/(loss)	2,200	0	4,600
Other comprehensive income/(loss), net of tax	20,900	(8,300)	(53,700)
Balance	$ (149,000)	$ (169,900)	$ (161,600)