STOCK BASED COMPENSATION - Outstanding and Exercisable Options (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Weighted average remaining contractual life of outstanding options	5 years 3 months	5 years 8 months 12 days	6 years 1 month 6 days
Total aggregate intrinsic value of outstanding options	$ 25,100	$ 162,400	$ 269,900
Weighted average remaining contractual life of exercisable options	4 years 4 months 24 days	4 years 8 months 12 days	5 years 1 month 6 days
Total aggregate intrinsic value of exercisable options	$ 25,100	$ 130,600	$ 178,300