RESTRUCTURING AND OTHER RELATED CHARGES (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Restructuring Cost and Reserve [Line Items]
Restructuring and other related charges, net	$ 0	$ 2,411	$ 208	$ 2,411
OneTeam Program
Restructuring Cost and Reserve [Line Items]
Restructuring and other related charges, net	0	2,411	208	2,411
OneTeam Program | Employee Severance
Restructuring Cost and Reserve [Line Items]
Restructuring and other related charges, net			208
Exit activities, costs incurred to date	6,900		6,900
OneTeam Program | Employee Severance | IHT
Restructuring Cost and Reserve [Line Items]
Restructuring and other related charges, net	26	967	128	967
OneTeam Program | Employee Severance | MS
Restructuring Cost and Reserve [Line Items]
Restructuring and other related charges, net	32	331	117	331
OneTeam Program | Employee Severance | Quest Integrity
Restructuring Cost and Reserve [Line Items]
Restructuring and other related charges, net	0	33	0	33
OneTeam Program | Employee Severance | Corporate and shared support services
Restructuring Cost and Reserve [Line Items]
Restructuring and other related charges, net	$ (58)	$ 1,080	$ (37)	$ 1,080