SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES AND PRACTICES - Additional Information (Details) $ in Thousands		3 Months Ended
	Dec. 01, 2018 USD ($)	Mar. 31, 2019 USD ($) employee country segment Location customer	Mar. 31, 2018 USD ($)	Dec. 31, 2018 USD ($)
Accounting Policies [Abstract]
Number of operating segments | segment		3
Number of locations in which company operates (more than) | Location		200
Number of countries in which the company operates | country		20
Number of employees (more than) | employee		7,200
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill impairment loss	$ 0
Goodwill		$ 281,655		$ 281,650
Accumulated impairment loss		75,200		75,200
Income Tax Disclosure [Abstract]
Provision (benefit) for income taxes		333	$ (4,958)
Pre-tax loss		$ 23,895	$ 17,222
Sales Revenue, Net | Customer Concentration Risk
Significant Accounting Policies [Line Items]
Number of customers accounted for more than specified percentage of consolidated revenues | customer		0
IHT
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill		$ 192,811		192,608
Accumulated impairment loss		21,100		21,100
MS
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill		55,420		55,627
Accumulated impairment loss		$ 54,100		$ 54,100