STOCK BASED COMPENSATION - Outstanding and Exercisable Options (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Weighted average remaining contractual life of outstanding options	5 years 8 months 12 days	6 years 1 month 6 days	6 years 7 months 6 days
Total aggregate intrinsic value of outstanding options	$ 162,400	$ 269,900	$ 254,200
Weighted average remaining contractual life of exercisable options	4 years 8 months 12 days	5 years 1 month 6 days	5 years 3 months 18 days
Total aggregate intrinsic value of exercisable options	$ 130,600	$ 178,300	$ 161,100