v3.6.0.2
Summary of significant accounting policies - Basis of presentation and consolidation (Details) - USD ($)
$ in Thousands
12 Months Ended
Aug. 04, 2015
Dec. 31, 2015
Dec. 31, 2016
Jan. 01, 2016
Aug. 03, 2015
Principles of consolidation          
Reduction to additional paid-in capital resulting from purchase of remaining noncontrolling interest   $ 1,150      
ASU 2016-09 | Early adoption          
Basis of presentation          
Increase to additional paid-in capital and accumulated deficit due to cumulative effect of a change in accounting principle       $ 94  
ASU 2016-09 | Early adoption | Federal          
Basis of presentation          
Increase to deferred tax assets       6,933  
ASU 2016-09 | Early adoption | State          
Basis of presentation          
Increase to deferred tax assets       $ 589  
Concourse Communications Detroit, LLC          
Principles of consolidation          
Percentage of additional ownership in subsidiary acquired 30.00%        
Total purchase price $ 1,150        
Reduction to additional paid-in capital resulting from purchase of remaining noncontrolling interest $ 1,150        
Chicago Concourse Development Group, LLC          
Principles of consolidation          
Percentage of ownership in subsidiaries     70.00%    
Boingo Holding Participacoes Ltda.          
Principles of consolidation          
Percentage of ownership in subsidiaries     75.00%    
Concourse Communications Detroit, LLC          
Principles of consolidation          
Percentage of ownership in subsidiaries         70.00%