BUSINESS SEGMENT INFORMATION - Segment (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021
Revenues:
Revenues	$ 459,601	$ 225,310	$ 1,119,732	$ 596,677
Operating income (loss):
Operating income (loss)	92,170	7,974	175,620	(3,767)
Interest expense	(143)	(1,280)	(543)	(1,763)
Interest income	329	15	472	47
Other (expense) income, net	(67)	448	516	1,571
Income (loss) before income taxes	92,289	7,157	176,065	(3,912)
Depreciation and amortization	20,941	18,106	60,501	53,775
Capital expenditures			90,227	44,925
Identifiable assets	1,055,583	826,640	1,055,583	826,640	$ 864,365
Technical Services
Revenues:
Revenues	435,775	211,842	1,058,227	560,602
Operating income (loss):
Operating income (loss)	89,455	8,272	171,093	3,938
Depreciation and amortization			53,002	46,341
Capital expenditures			79,828	38,794
Identifiable assets	836,310	556,385	836,310	556,385
Support Services
Revenues:
Revenues	23,826	13,468	61,505	36,075
Operating income (loss):
Operating income (loss)	5,278	(55)	11,392	(5,353)
Depreciation and amortization			7,346	7,232
Capital expenditures			9,558	5,436
Identifiable assets	79,546	74,135	79,546	74,135
Corporate
Operating income (loss):
Operating income (loss)	(4,106)	(3,080)	(13,160)	(9,760)
Depreciation and amortization			153	202
Capital expenditures			841	695
Identifiable assets	139,727	196,120	139,727	196,120
Gain on disposition of assets, net.
Operating income (loss):
Operating income (loss)	$ 1,543	$ 2,837	$ 6,295	$ 7,408