SELECTED QUARTERLY FINANCIAL DATA (UNAUDITED) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Selected Quarterly Financial Information [Abstract]
Revenue	$ 243,745	$ 247,224	$ 246,897	$ 244,357	$ 239,744	$ 231,458	$ 230,111	$ 221,341	$ 982,223	$ 922,654	$ 696,473
Gross profit	65,909	65,233	64,818	64,955	63,678	62,687	62,249	62,139	260,915	250,753	206,650
Loss from continuing operations, before income taxes	(15,980)	(28,791)	(264,822)	(15,367)	(60,626)	(37,274)	(17,221)	(23,606)	(324,960)	(138,727)	(70,381)
Income from discontinued operations, net of income taxes	(1,451)	7,457	94	(2,379)	(291)	494	466	1,783	3,721	2,452	1,987
Net loss	$ (18,443)	$ (16,783)	$ (244,807)	$ (19,674)	$ (63,626)	$ (38,710)	$ (19,818)	$ (25,314)	$ (299,707)	$ (147,468)	$ (69,654)
Loss from continuing operations, basic and diluted (in USD per share)	$ (0.28)	$ (0.38)	$ (3.62)	$ (0.28)	$ (0.92)	$ (0.57)	$ (0.30)	$ (0.40)	$ (4.56)	$ (2.19)	$ (1.11)
Income (loss) from discontinued operations, basic and diluted (in USD per share)	(0.02)	0.11	0.00	(0.03)	0.00	0.01	0.01	0.03	0.05	0.04	0.03
Income (loss), basic and diluted (in USD per share)	$ (0.30)	$ (0.27)	$ (3.62)	$ (0.31)	$ (0.92)	$ (0.56)	$ (0.29)	$ (0.37)	$ (4.51)	$ (2.15)	$ (1.08)