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Basis of Presentation and Summary of Significant Accounting Policies (Concentration Risk) (Details) - customer
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Sales      
Concentration Risk [Line Items]      
Concentration risk, customers above benchmark, number 0 0 0
Accounts Receivable      
Concentration Risk [Line Items]      
Concentration risk, customers above benchmark, number 0 0  
Minimum | Customer Concentration Risk | Sales      
Concentration Risk [Line Items]      
Percentage of concentration risk 5.00% 5.00% 5.00%
Minimum | Customer Concentration Risk | Accounts Receivable      
Concentration Risk [Line Items]      
Percentage of concentration risk 5.00% 5.00%