ACCUMULATED OTHER COMPREHENSIVE LOSS - Summary of Changes in Accumulated Other Comprehensive Loss Included Within Shareholders' Equity (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Accumulated Other Comprehensive Loss [Line Items]
Balance, beginning of period			$ 535,637
Other comprehensive income (loss) before tax	$ 3,386	$ (1,282)	8,861	$ 1,525
Other comprehensive income (loss), tax	(1,065)	287	(2,295)	(1,031)
Other comprehensive income (loss)	2,321	(995)	6,566	494
Balance, end of period	453,504		453,504
Foreign currency translation adjustments
Accumulated Other Comprehensive Loss [Line Items]
Balance, beginning of period			(31,973)	(28,124)
Other comprehensive income (loss) before tax			10,406	1,872
Other comprehensive income (loss), tax			(2,894)	(1,147)
Balance, end of period	(21,567)	(26,252)	(21,567)	(26,252)
Foreign currency hedge
Accumulated Other Comprehensive Loss [Line Items]
Balance, beginning of period			5,048	4,567
Other comprehensive income (loss) before tax			(1,598)	(347)
Other comprehensive income (loss), tax			610	116
Balance, end of period	3,450	4,220	3,450	4,220
Defined benefit pension plans
Accumulated Other Comprehensive Loss [Line Items]
Balance, beginning of period			(10,518)
Other comprehensive income (loss) before tax			53	0
Other comprehensive income (loss), tax			(11)	0
Balance, end of period	(10,465)		(10,465)
Tax provision
Accumulated Other Comprehensive Loss [Line Items]
Balance, beginning of period			8,443	5,183
Other comprehensive income (loss), tax			(2,295)	(1,031)
Balance, end of period	6,148	4,152	6,148	4,152
Accumulated other comprehensive loss
Accumulated Other Comprehensive Loss [Line Items]
Balance, beginning of period			(29,000)	(18,374)
Other comprehensive income (loss)			6,566	494
Balance, end of period	$ (22,434)	$ (17,880)	$ (22,434)	$ (17,880)