ENTITY WIDE DISCLOSURES - Geographic Breakdown of Revenues and Total Assets (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenues	$ 250,854	$ 192,407
Total assets	1,180,554		$ 798,991
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenues	202,053	148,964
Total assets	970,902		682,124
Canada
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenues	21,985	23,702
Total assets	61,911		59,626
Europe
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenues	16,889	12,071
Total assets	96,434		33,271
Other foreign countries
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenues	9,927	$ 7,670
Total assets	$ 51,307		$ 23,970