DESCRIPTION OF THE COMPANY AND NATURE OF OPERATIONS - Narrative (Details) $ in Thousands, ft² in Millions	12 Months Ended
	Dec. 31, 2017 USD ($) ft² Service_Point Data_Center point_of_presence	Dec. 31, 2016 USD ($)
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Number of metropolitan markets (market) | Data_Center	21
Number of datacenters (datacenter) | Service_Point	56
Number of POPs (point of presence) | point_of_presence	97
Area under lease (sqft) | ft²	1.0
Area of data centers (sqft) | ft²	0.5
Accumulated deficit | $	$ 1,323,723	$ 1,278,699
Working capital deficit | $	$ 22,400