v3.7.0.1
Stock incentive plans - Compensation expense (Details) - USD ($)
$ in Thousands
3 Months Ended 6 Months Ended
Jun. 30, 2017
Jun. 30, 2016
Jun. 30, 2017
Jun. 30, 2016
Recognized stock-based compensation expense        
Total stock-based compensation $ 4,288 $ 3,079 $ 7,332 $ 6,684
Stock-based compensation expense capitalized 173 189 367 371
Network operations        
Recognized stock-based compensation expense        
Total stock-based compensation 562 531 1,108 1,177
Development and technology        
Recognized stock-based compensation expense        
Total stock-based compensation 280 251 550 563
Selling and marketing        
Recognized stock-based compensation expense        
Total stock-based compensation 639 458 1,065 1,007
General and administrative        
Recognized stock-based compensation expense        
Total stock-based compensation $ 2,807 $ 1,839 $ 4,609 $ 3,937