CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Income Statement [Abstract]
Net revenues	$ 82,972	$ 68,907	$ 239,135	$ 210,682
Operating costs and expenses:
Costs of sales and services, exclusive of depreciation and amortization	28,866	24,945	81,880	80,419
Costs of customer support	7,984	6,237	24,212	19,634
Sales, general and administrative	18,170	15,331	57,625	47,466
Depreciation and amortization	23,431	20,917	67,097	57,596
Exit activities, restructuring and impairments	2,347	745	3,140	6,396
Total operating costs and expenses	80,798	68,175	233,954	211,511
Income from operations	2,174	732	5,181	(829)
Interest expense	16,898	12,299	47,786	37,581
Loss on foreign currency, net	195	197	5	485
Total non-operating expenses	17,093	12,496	47,791	38,066
Loss before income taxes, non-controlling interest and equity in earnings of equity-method investment	(14,919)	(11,764)	(42,610)	(38,895)
Provision for income taxes	162	221	404	689
Equity in earnings of equity-method investment, net of taxes	0	(1,122)	0	(1,207)
Net loss	(15,081)	(10,863)	(43,014)	(38,377)
Less net income attributable to non-controlling interest	25	32	75	32
Net loss attributable to INAP stockholders	(15,106)	(10,895)	(43,089)	(38,409)
Other comprehensive (loss) income:
Foreign currency translation adjustment	(98)	(91)	24	14
Unrealized gain on foreign currency contracts	0	0	0	145
Total other comprehensive (loss) income	(98)	(91)	24	159
Comprehensive loss	$ (15,204)	$ (10,986)	$ (43,065)	$ (38,250)
Basic and diluted net loss per share (in dollars per share)	$ (0.75)	$ (0.56)	$ (2.16)	$ (2.04)
Weighted average shares outstanding used in computing basic and diluted net loss per share (in shares)	20,206	19,929	19,968	18,645