Segment Information (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015 USD ($)	Jun. 30, 2014 USD ($)	Jun. 30, 2015 USD ($) item	Jun. 30, 2014 USD ($)
Segment Information
Number of reportable segments | item			2
Segment Information
Operating revenues	$ 96,187	$ 96,784	$ 193,303	$ 193,856
Depreciation and amortization	21,941	18,884	43,221	37,604
Operating income (loss)	5,260	7,892	11,181	16,030
Capital expenditures			46,955	51,061
Telecommunications
Segment Information
Operating revenues	93,812	94,700	188,649	189,576
Depreciation and amortization	21,374	18,467	42,102	36,781
Operating income (loss)	5,570	8,126	11,818	16,166
Capital expenditures			46,377	50,716
Data center colocation services
Segment Information
Operating revenues	2,784	2,323	5,381	4,728
Depreciation and amortization	567	417	1,119	823
Operating income (loss)	(310)	(234)	(637)	(136)
Capital expenditures			578	345
Intersegment Elimination
Segment Information
Operating revenues	$ (409)	$ (239)	$ (727)	$ (448)