SEGMENT AND GEOGRAPHICAL INFORMATION - Revenue by Geography (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	$ 438,533	$ 310,013	$ 817,802	$ 560,570
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	421,808	299,326	789,387	542,282
International
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	$ 16,725	$ 10,687	$ 28,415	$ 18,288