FAIR VALUE MEASUREMENTS - Fair Value of Assets and Liabilities Measured on Recurring Basis (Details) - Fair Value, Measurements, Recurring - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Net Investment Hedge
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Net liabilities	$ (3,933)	$ (5,048)
Contingent Consideration
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Net liabilities	1,555	3,739
Quoted Prices in Active Markets for Identical Items (Level 1) | Net Investment Hedge
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Net liabilities	0	0
Quoted Prices in Active Markets for Identical Items (Level 1) | Contingent Consideration
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Net liabilities	0	0
Significant Other Observable Inputs (Level 2) | Net Investment Hedge
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Net liabilities	(3,933)	(5,048)
Significant Other Observable Inputs (Level 2) | Contingent Consideration
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Net liabilities	0	0
Significant Unobservable Inputs (Level 3) | Net Investment Hedge
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Net liabilities	0	0
Significant Unobservable Inputs (Level 3) | Contingent Consideration
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Net liabilities	$ 1,555	$ 3,739