Property and equipment (Details 2) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Depreciation, Depletion and Amortization
Total depreciation and amortization of property and equipment	$ 10,033	$ 7,335	$ 27,899	$ 19,650
Network access
Depreciation, Depletion and Amortization
Total depreciation and amortization of property and equipment	6,277	5,027	17,264	13,400
Network operations
Depreciation, Depletion and Amortization
Total depreciation and amortization of property and equipment	2,087	1,370	5,916	3,739
Development and Technology
Depreciation, Depletion and Amortization
Total depreciation and amortization of property and equipment	1,377	852	3,887	2,331
General and administrative
Depreciation, Depletion and Amortization
Total depreciation and amortization of property and equipment	$ 292	$ 86	$ 832	$ 180