SELECTED QUARTERLY FINANCIAL DATA (UNAUDITED) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	12 Months Ended
Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Selected Quarterly Financial Information [Abstract]
Net revenue	$ 183,568	$ 180,962	$ 175,789	$ 168,584	$ 182,582	$ 198,692	$ 218,106	$ 217,810	$ 708,903	$ 817,190	$ 935,589
Gross profit	62,122	65,911	59,957	55,048	70,194	66,563	67,611	64,874	243,038	269,242	262,082
Loss from continuing operations, before income taxes	(15,003)	(8,001)	(15,081)	(12,939)	(7,202)	(12,998)	(28,432)	(18,801)	(51,024)	(67,433)	(34,157)
Income (loss) from discontinued operations, net of income taxes	15	(71)	(15)	(30)	(287)	66	(373)	(299)	(101)	(893)	(6,593)
Net loss	$ (15,363)	$ (8,174)	$ (15,139)	$ (13,017)	$ (1,962)	$ (12,992)	$ (29,523)	$ (19,719)	$ (51,693)	$ (64,196)	$ (42,765)
Loss from continuing operations, basic and diluted (in USD per share)	$ (0.14)	$ (0.09)	$ (0.14)	$ (0.12)	$ (0.03)	$ (0.12)	$ (0.26)	$ (0.18)	$ (0.49)	$ (0.59)	$ (0.48)
Income (loss) from discontinued operations, basic and diluted (in USD per share)	0.00	0.00	0.00	0.00	(0.01)	0.00	0.00	0.00	0.00	(0.01)	(0.07)
Loss per common share, basic and diluted (in USD per share)	$ (0.14)	$ (0.09)	$ (0.14)	$ (0.12)	$ (0.04)	$ (0.12)	$ (0.26)	$ (0.18)	$ (0.49)	$ (0.60)	$ (0.55)

The amount of net income or loss for the period per each share in instances when basic and diluted earnings per share are the same amount and reported as a single line item on the face of the financial statements. Basic earnings per share is the amount of net income or loss for the period per each share of common stock or unit outstanding during the reporting period. Diluted earnings per share includes the amount of net income or loss for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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Amount of income (loss) from continuing operations before deduction of income tax expense (benefit) and income (loss) attributable to noncontrolling interest, and addition of income (loss) from equity method investments.

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