QUARTERLY FINANCIAL INFORMATION - Summary of Quarterly Results (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Quarterly Financial Information Disclosure [Abstract]
Total revenue	$ 557,737	$ 609,469	$ 640,994	$ 644,838	$ 569,929	$ 627,964	$ 673,218	$ 668,905	$ 2,453,038	$ 2,540,016	$ 2,683,298
Gross profit	177,547	196,806	212,723	212,971	170,168	215,408	238,698	235,845	800,047	860,119	984,643
Operating income (loss)	(394,231)	40,445	39,820	53,553	(448,129)	64,893	116,224	94,065	(260,413)	(172,947)	393,107
Net (loss) income	$ (209,825)	$ 21,463	$ 15,661	$ 23,850	$ (433,447)	$ 32,354	$ 64,028	$ 50,815	$ (148,851)	$ (286,250)	$ 219,299
Weighted average shares outstanding:
Basic (in shares)	70,251	68,354	68,287	68,246	68,219	68,190	68,176	73,078	68,789	69,409	83,927
Diluted (in shares)	70,251	68,569	68,362	68,300	68,219	68,315	68,303	73,373	68,789	69,409	84,186
Earnings per share:
Basic (in USD per share)	$ (2.99)	$ 0.31	$ 0.23	$ 0.35	$ (6.35)	$ 0.47	$ 0.94	$ 0.70	$ (2.16)	$ (4.12)	$ 2.61
Diluted (in USD per share)	$ (2.99)	$ 0.31	$ 0.23	$ 0.35	$ (6.35)	$ 0.47	$ 0.94	$ 0.69	$ (2.16)	$ (4.12)	$ 2.60