SEGMENT AND GEOGRAPHIC DISCLOSURES - Segment Data for our Three Operating Segments (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Dec. 31, 2021	Sep. 30, 2021	Mar. 31, 2021
Segment Reporting Information [Line Items]
Revenues	$ 218,576			$ 194,618
Operating income (loss)	(16,203)			(24,300)
Capital expenditures	6,631			4,397
Depreciation and amortization	10,031			10,959
IHT
Segment Reporting Information [Line Items]
Revenues	95,595			91,139
MS
Segment Reporting Information [Line Items]
Revenues	93,441			87,396
Goodwill impairment charges			$ 55,800
Quest Integrity
Segment Reporting Information [Line Items]
Revenues	29,540			16,083
Goodwill impairment charges		$ 8,800
Operating segments | IHT
Segment Reporting Information [Line Items]
Revenues	95,595			91,139
Operating income (loss)	134			364
Capital expenditures	4,771			2,714
Depreciation and amortization	3,254			3,470
Operating segments | MS
Segment Reporting Information [Line Items]
Revenues	93,441			87,396
Operating income (loss)	513			115
Capital expenditures	813			1,152
Depreciation and amortization	4,884			5,439
Operating segments | Quest Integrity
Segment Reporting Information [Line Items]
Revenues	29,540			16,083
Operating income (loss)	6,204			(252)
Capital expenditures	1,009			406
Depreciation and amortization	577			712
Corporate and shared support services
Segment Reporting Information [Line Items]
Operating income (loss)	(23,054)			(24,527)
Capital expenditures	38			125
Depreciation and amortization	$ 1,316			$ 1,338