ACCUMULATED OTHER COMPREHENSIVE INCOME/(LOSS) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Apr. 02, 2016
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax
Equity, beginning balance	$ 615,088
Other comprehensive income	8,894	$ 13,501
Equity, ending balance	637,808
Tax (benefit)/expense	300	300
Foreign Currency Translation Adjustments
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax
Equity, beginning balance	(118,400)	(110,100)
Other comprehensive income/(loss) before reclassifications	8,400	13,000
Amounts reclassified from accumulated other comprehensive income/(loss) (1)	0	0
Other comprehensive income	8,400	13,000
Equity, ending balance	(110,000)	(97,100)
Pension and Post-Retirement Plan Benefit Adjustments
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax
Equity, beginning balance	(51,500)	(51,500)
Other comprehensive income/(loss) before reclassifications	0	0
Amounts reclassified from accumulated other comprehensive income/(loss) (1)	500	400
Other comprehensive income	500	400
Equity, ending balance	(51,000)	(51,100)
AOCI Including Portion Attributable to Noncontrolling Interest
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax
Equity, beginning balance	(169,900)	(161,600)
Other comprehensive income/(loss) before reclassifications	8,400	13,000
Amounts reclassified from accumulated other comprehensive income/(loss) (1)	500	400
Other comprehensive income	8,900	13,400
Equity, ending balance	$ (161,000)	$ (148,200)