Unaudited Condensed Consolidated Statements of Operations - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Revenues	$ 290,856	$ 285,067	$ 937,130	$ 883,877
Operating expenses	220,717	216,126	694,275	655,489
Gross margin	70,139	68,941	242,855	228,388
Selling, general and administrative expenses	87,786	85,179	270,619	265,557
Restructuring and other related charges, net	2,047	2,637	4,458	1,661
Gain on revaluation of contingent consideration	0	0	(202)	(1,174)
Goodwill impairment loss	0	75,241	0	75,241
Operating loss	(19,694)	(94,116)	(32,020)	(112,897)
Interest expense, net	8,022	6,369	23,250	13,899
Write-off of deferred loan costs	0	1,244	0	1,244
Loss (gain) on convertible debt embedded derivative	0	(6,292)	24,783	(6,292)
Other expense, net	123	157	455	515
Loss before income taxes	(27,839)	(95,594)	(80,508)	(122,263)
Less: Income tax benefit	(4,977)	(12,066)	(7,331)	(18,141)
Net loss	$ (22,862)	$ (83,528)	$ (73,177)	$ (104,122)
Basic loss per share	$ (0.76)	$ (2.80)	$ (2.44)	$ (3.49)
Diluted loss per share	$ (0.76)	$ (2.80)	$ (2.44)	$ (3.49)