CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (DEFICIT) - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock	Additional Paid-In Capital	Treasury Stock	Accumulated Deficit	Accumulated Items of Other Comprehensive Loss	Non-Controlling Interest	2017 Securities Purchase Agreement	2017 Securities Purchase Agreement Common Stock	2017 Securities Purchase Agreement Additional Paid-In Capital	2018 Public Offering	2018 Public Offering Common Stock	2018 Public Offering Additional Paid-In Capital
Balance (in shares) at Dec. 31, 2015		13,993
Balance at Dec. 31, 2015	$ 114,436	$ 14	$ 1,277,553	$ (6,393)	$ (1,153,957)	$ (2,781)	$ 0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(124,742)				(124,742)
Net income attributable to non-controlling interest	0
Foreign currency translation	(39)					(39)
Interest rate swap	728					728
Foreign currency contracts	600					600
Common stock issuance (in shares)		444
Employee taxes paid on withholding shares (in shares)		(62)
Employee taxes paid on withholding shares	(530)			(530)
Stock-based compensation	5,148		5,148
Proceeds from exercise of stock options, net (in shares)		75
Proceeds from exercise of stock options, net	675		675	0
Balance (in shares) at Dec. 31, 2016		14,450
Balance at Dec. 31, 2016	(3,724)	$ 14	1,283,376	(6,923)	(1,278,699)	(1,492)	0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(45,273)				(45,273)
Net income attributable to non-controlling interest	(70)				(70)		70
Foreign currency translation	23					23
Interest rate swap	0
Foreign currency contracts	145					145
INAP Japan	3,999						3,999
Common stock issuance (in shares)		379							5,951
Common stock issuance								$ 40,163	$ 7	$ 40,156
Employee taxes paid on withholding shares (in shares)		(25)
Employee taxes paid on withholding shares	(236)			(236)
Stock-based compensation	3,121		3,121
Proceeds from exercise of stock options, net (in shares)		49
Proceeds from exercise of stock options, net	$ 431		431
Balance (in shares) at Dec. 31, 2017	20,804	20,804
Balance at Dec. 31, 2017	$ (1,032)	$ 21	1,327,084	(7,159)	(1,323,723)	(1,324)	4,069
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(62,375)				(62,375)
Net income attributable to non-controlling interest	(125)				(125)		125
Foreign currency translation	259					259
Interest rate swap	0
Foreign currency contracts	0
INAP Japan	(1,400)						(1,400)
Common stock issuance (in shares)		471										4,210
Common stock issuance											$ 37,103	$ 4	$ 37,099
Employee taxes paid on withholding shares (in shares)		(36)
Employee taxes paid on withholding shares	(487)			(487)
Stock-based compensation	4,737		4,737
Proceeds from exercise of stock options, net (in shares)		6
Proceeds from exercise of stock options, net	$ 48		48
Balance (in shares) at Dec. 31, 2018	25,455	25,455
Balance at Dec. 31, 2018	$ 57	$ 25	$ 1,368,968	$ (7,646)	$ (1,363,019)	$ (1,065)	$ 2,794