Condensed Consolidated Statements of Operations - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Income Statement [Abstract]
Revenues	$ 142,249	$ 101,946	$ 283,421	$ 266,496
Cost of revenues	124,106	112,290	244,097	258,374
Selling, general and administrative expenses	22,980	20,937	43,891	45,633
Other operating income, net	(1,590)	(742)	(1,864)	(1,086)
Operating loss	(3,247)	(30,539)	(2,703)	(36,425)
Foreign currency exchange (gain) loss	224	781	(108)	2,763
Interest expense, net	2,164	2,912	4,572	6,113
(Gain) loss on extinguishment of debt	0	(1,334)	790	(419)
Loss before income taxes	(5,635)	(32,898)	(7,957)	(44,882)
Provision (benefit) for income taxes	363	(6,654)	3,403	(6,490)
Net loss	$ (5,998)	$ (26,244)	$ (11,360)	$ (38,392)
Net loss per common share - basic: (in dollars per share)	$ (0.07)	$ (0.29)	$ (0.12)	$ (0.43)
Net loss per common share - diluted: (in dollars per share)	$ (0.07)	$ (0.29)	$ (0.12)	$ (0.43)