FAIR VALUE OF FINANCIAL ASSETS AND LIABILITIES - Reconciliation of Beginning and Ending Balances (Details) - Fair Value, Measurements, Recurring - Fair Value, Inputs, Level 3 - Contingent Consideration Liability $ in Thousands	6 Months Ended
	Jun. 30, 2019 USD ($)
Contingent Liability for Accrued Consideration
Beginning balance at December 31, 2018	$ 4,319
Acquisitions and settlements
Acquisitions	0
Settlements	(1,500)
Total remeasurement adjustments:
Changes in fair value recorded in other (income) expense, net	66
Ending Balance at June 30, 2019	2,885
The amount of total losses for the quarter included in earnings or changes to net assets, attributable to changes in unrealized losses relating to liabilities still held at June 30, 2019.	$ 66