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Basis of Presentation (Details)
$ in Thousands
3 Months Ended
Mar. 31, 2020
USD ($)
customer
item
Mar. 31, 2019
USD ($)
customer
Customer concentration    
Number of top customers 10  
Number of calendar years in which top customers typically generate minimum specified percentage of revenue | item 1  
Minimum percentage of revenues generated by top ten customers 50.00%  
Revenue | $ $ 743,243 $ 661,558
Revenues | Customer concentration | Top ten customers    
Customer concentration    
Number of top customers 10 10
Percentage of concentration risk 50.10% 49.10%
Revenues | Customer concentration | Pipeline Customer [Member]    
Customer concentration    
Percentage of concentration risk 11.30%  
Number of customers 1