v3.10.0.1
Deferred Revenue - Classification of Deferred Revenue (Details) - USD ($)
$ in Thousands
Dec. 31, 2018
Dec. 31, 2017
Jan. 01, 2017
Dec. 31, 2016
Revenue from Contract with Customer [Abstract]        
Current portion $ 39,180 $ 30,694 $ 20,164  
Long term portion 1,881 1,352 $ 922  
Deferred revenue $ 41,061 $ 32,046   $ 21,086