Quarterly report pursuant to Section 13 or 15(d)

Accounting Policies - Revenue Recognition (Details)

v3.19.1
Accounting Policies - Revenue Recognition (Details) - USD ($)
$ in Thousands
3 Months Ended
Mar. 31, 2019
Dec. 31, 2018
Revenue Recognition    
Customer contract period 90 days  
Contract Liabilities    
Deferred revenue $ 17,081 $ 19,963
Receivables, net    
Contract Assets    
Receivables, unbilled 58,328 61,339
Accrued liabilities    
Contract Liabilities    
Deferred revenue $ 17,081 $ 19,963