Condensed Consolidated Statements of Operations (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Operating Income (Loss) [Abstract]
Revenues	$ 115,315	$ 163,644	$ 229,859	$ 372,108
Cost of revenues	102,803	142,155	214,376	318,789
Selling, general and administrative expenses	21,435	23,963	44,927	49,941
Other operating income, net	(713)	(792)	(2,409)	(1,068)
Impairments and other charges	6,925	0	6,925	0
Operating income (loss)	(15,135)	(1,682)	(33,960)	4,446
Foreign currency exchange (gain) loss	(746)	(410)	(1,201)	1,154
Interest expense, net	3,022	2,224	5,103	4,479
Gain on extinguishment of debt	0	0	(1,894)	0
Loss from operations before income taxes	(17,411)	(3,496)	(35,968)	(1,187)
Provision (benefit) for income taxes	(3,507)	758	(8,764)	2,074
Net loss	$ (13,904)	$ (4,254)	$ (27,204)	$ (3,261)
Loss per common share - basic (in dollars per share)	$ (0.17)	$ (0.05)	$ (0.33)	$ (0.04)
Loss per common share - diluted (in dollars per share)	$ (0.17)	$ (0.05)	$ (0.33)	$ (0.04)