REVENUES - Summary of Revenue by Geography (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Disaggregation of Revenue [Line Items]
Net revenues	$ 72,878	$ 82,972	$ 219,576	$ 239,135
INAP US
Disaggregation of Revenue [Line Items]
Net revenues	56,947	65,678	171,928	186,821
INAP INTL
Disaggregation of Revenue [Line Items]
Net revenues	15,931	17,294	47,648	52,314
INAP US
Disaggregation of Revenue [Line Items]
Net revenues	57,939	66,752	174,964	190,071
INAP INTL
Disaggregation of Revenue [Line Items]
Net revenues	14,939	16,220	44,612	49,064
UNITED STATES | INAP US
Disaggregation of Revenue [Line Items]
Net revenues	57,939	66,752	174,964	190,071
UNITED STATES | INAP INTL
Disaggregation of Revenue [Line Items]
Net revenues	0	0	0	0
CANADA | INAP US
Disaggregation of Revenue [Line Items]
Net revenues	0	0	0	0
CANADA | INAP INTL
Disaggregation of Revenue [Line Items]
Net revenues	8,181	9,187	24,208	27,846
Other Non-Us | INAP US
Disaggregation of Revenue [Line Items]
Net revenues	0	0	0	0
Other Non-Us | INAP INTL
Disaggregation of Revenue [Line Items]
Net revenues	$ 6,758	$ 7,033	$ 20,404	$ 21,218