SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES AND PRACTICES - Schedule of Rollforward Goodwill (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Goodwill [Roll Forward]
Balance at beginning of period	$ 281,650	$ 284,804
Foreign currency adjustments	356	(2,893)
Disposal		(261)
Balance at end of period	282,006	281,650
IHT
Goodwill [Roll Forward]
Balance at beginning of period	192,608	194,211
Foreign currency adjustments	608	(1,603)
Disposal		0
Balance at end of period	193,216	192,608
MS
Goodwill [Roll Forward]
Balance at beginning of period	55,627	56,600
Foreign currency adjustments	(218)	(712)
Disposal		(261)
Balance at end of period	55,409	55,627
Quest Integrity
Goodwill [Roll Forward]
Balance at beginning of period	33,415	33,993
Foreign currency adjustments	(34)	(578)
Disposal		0
Balance at end of period	$ 33,381	$ 33,415