FAIR VALUE DISCLOSURES - Reconciliation of Contingent Consideration Liability and Asset (Details) - USD ($) $ in Thousands	1 Months Ended	12 Months Ended
	Nov. 30, 2017	Dec. 31, 2017	Dec. 31, 2016
Business Combination, Contingent Consideration, Liability [Abstract]
Decrease in contingent consideration liability		$ 400	$ 1,500
Payment of contingent consideration	$ (400)
Recurring | Level 3
Business Combination, Contingent Consideration, Liability [Abstract]
Beginning balance		818	2,700
Decrease in contingent consideration liability		(426)	(1,876)
Payment of contingent consideration		(382)
Foreign currency translation		(10)	(6)
Ending balance		0	818
Business Combination, Contingent Consideration, Asset [Abstract]
Beginning balance		$ 0	350
Decrease in contingent consideration asset			(350)
Ending balance			$ 0