FAIR VALUE OF FINANCIAL ASSETS AND LIABILITIES - Narrative (Details) $ in Thousands	Sep. 30, 2018 USD ($)	Jan. 01, 2018 USD ($)
Valuation Technique, Discounted Cash Flow | Fair Value, Inputs, Level 3 | Annualized EBITDA and probability of achievement
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liability for contingent consideration	$ 4,084
Discount rate	0.076
ASI
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liability for contingent consideration		$ 4,000
ASI | Other Current and Long-term Liabilities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liability for contingent consideration	$ 4,100