SEGMENT AND GEOGRAPHIC INFORMATION - Total Revenue by Major Geographic Area (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Segment Reporting Information [Line Items]
Total Revenues	$ 357,082	$ 258,636
United States
Segment Reporting Information [Line Items]
Total Revenues	248,928	201,096
Europe
Segment Reporting Information [Line Items]
Total Revenues	51,773	28,816
Asia Pacific
Segment Reporting Information [Line Items]
Total Revenues	35,785	16,088
Rest of World
Segment Reporting Information [Line Items]
Total Revenues	$ 20,596	$ 12,636