CONDENSED CONSOLDIATED STATEMENTS OF COMPREHENSIVE (LOSS) INCOME (unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Revenues [Abstract]
Revenue	$ 60,109	$ 181,820	$ 157,492	$ 443,958
COST AND EXPENSES
Selling, general and administrative (Note 11)	13,528	8,796	24,084	25,698
Selling, general and administrative - related parties (Note 11)	198	659	413	1,093
Depreciation, depletion, amortization and accretion	24,116	30,145	49,998	58,721
Impairment of goodwill	0	0	54,973	0
Impairment of other long-lived assets	0	0	12,897	0
Total cost and expenses	86,595	207,615	273,024	442,597
Operating (loss) income	(26,486)	(25,795)	(115,532)	1,361
OTHER INCOME (EXPENSE)
Interest expense, net	(1,471)	(1,551)	(3,109)	(2,074)
Other, net	8,137	4,019	15,546	28,576
Other, net - related parties	1,133	0	1,133	0
Total other income	7,799	2,468	13,570	26,502
(Loss) income before income taxes	(18,687)	(23,327)	(101,962)	27,863
(Benefit) provision for income taxes	(3,482)	(12,438)	(2,786)	10,419
Net (loss) income	(15,205)	(10,889)	(99,176)	17,444
OTHER COMPREHENSIVE (LOSS) INCOME
Foreign currency translation adjustment, net of tax of ($150), $211, $92 and $182, respectively, for the three and six months ended June 30, 2020 and three and six months ended June 30, 2019	668	350	(746)	706
Comprehensive (loss) income	$ (14,537)	$ (10,539)	$ (99,922)	$ 18,150
Net (loss) income per share (basic) (Note 15) (in USD per share)	$ (0.33)	$ (0.24)	$ (2.18)	$ 0.39
Net (loss) income per share (diluted) (Note 15) (In USD per share)	$ (0.33)	$ (0.24)	$ (2.18)	$ 0.39
Weighted average number of shares outstanding (basic) (Note 15) (in shares)	45,727	45,003	45,521	44,966
Weighted average number of shares outstanding (diluted) (Note 15) (in shares)	45,727	45,003	45,521	45,060
Dividends declared per share (in USD per share)	$ 0	$ 0.125	$ 0	$ 0.25
Services
Revenues [Abstract]
Revenue	$ 44,878	$ 115,760	$ 113,723	$ 308,861
COST AND EXPENSES
Cost of revenue	42,255	132,688	112,952	290,794
Products
Revenues [Abstract]
Revenue	4,706	18,362	13,356	30,671
COST AND EXPENSES
Cost of revenue	6,401	32,677	17,509	62,928
Related parties
COST AND EXPENSES
Selling, general and administrative - related parties (Note 11)	198	659	413	1,093
Related parties | Services
Revenues [Abstract]
Revenue	8,650	36,837	26,663	80,910
COST AND EXPENSES
Cost of revenue	97	2,650	198	3,363
Related parties | Products
Revenues [Abstract]
Revenue	$ 1,875	$ 10,861	$ 3,750	$ 23,516