Unaudited Condensed Consolidated Statements of Operations - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Income Statement [Abstract]
Revenues	$ 269,599	$ 302,385
Operating expenses	203,652	226,851
Gross margin	65,947	75,534
Selling, general and administrative expenses	82,267	89,659
Restructuring and other related charges, net	208	0
Operating loss	(16,528)	(14,125)
Interest expense, net	7,425	7,597
Gain on convertible debt embedded derivative (see Note 8)	0	(4,547)
Other (income) expense, net	(58)	47
Loss before income taxes	(23,895)	(17,222)
Less: Income tax expense (benefit)	333	(4,958)
Net loss	$ (24,228)	$ (12,264)
Basic loss per share	$ (0.80)	$ (0.41)
Diluted loss per share	$ (0.80)	$ (0.41)