v3.19.3.a.u2
Deferred Revenue - Changes in Deferred Revenue (Details) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Change in Contract with Customer, Liability [Roll Forward]    
Balance, beginning of the year $ 41,061 $ 32,046
Deferral of revenue 46,291 37,563
Deferred revenue from 6RS acquisition 8,901 0
Recognition of deferred revenue (33,593) (28,548)
Balance, end of the year $ 62,660 $ 41,061