Current report of foreign issuer pursuant to Rules 13a-16 and 15d-16 Amendments

Revenue Recognition (Narrative) (Details)

v3.10.0.1
Revenue Recognition (Narrative) (Details) - USD ($)
$ in Thousands
9 Months Ended
Sep. 30, 2018
Dec. 31, 2017
Deferred Revenue Arrangement [Line Items]    
Revenue recognized $ 44,200  
Deferred revenue noncurrent portion 16,009 $ 15,200
Increase in retained earnings effect on other non-current assets for the cumulative-effect adjustments 1,400  
Deferred sales commissions 2,500  
Next 12 Months [Member]    
Deferred Revenue Arrangement [Line Items]    
Revenue recognized 53,100  
Second Year [Member]    
Deferred Revenue Arrangement [Line Items]    
Revenue recognized 10,300  
There after [Member]    
Deferred Revenue Arrangement [Line Items]    
Revenue recognized $ 5,700