v3.10.0.1
Stock incentive plans - Compensation expense (Details) - USD ($)
$ in Thousands
3 Months Ended 9 Months Ended
Sep. 30, 2018
Sep. 30, 2017
Sep. 30, 2018
Sep. 30, 2017
Recognized stock-based compensation expense        
Total stock-based compensation expense $ 3,155 $ 3,684 $ 9,227 $ 11,016
Stock-based compensation expense capitalized 208 163 600 530
Network operations        
Recognized stock-based compensation expense        
Total stock-based compensation expense 549 552 1,602 1,660
Development and technology        
Recognized stock-based compensation expense        
Total stock-based compensation expense 323 275 915 825
Selling and marketing        
Recognized stock-based compensation expense        
Total stock-based compensation expense 511 524 1,377 1,589
General and administrative        
Recognized stock-based compensation expense        
Total stock-based compensation expense $ 1,772 $ 2,333 $ 5,333 $ 6,942