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Business Segment Data (Details)
6 Months Ended
Jun. 30, 2021
Jun. 30, 2020
Business Segment Data (Details) [Line Items]    
Number of Reportable Segments 2  
Customer Concentration Risk [Member] | Foreign [Member] | Revenue Benchmark [Member]    
Business Segment Data (Details) [Line Items]    
Concentration Risk, Percentage 10.00% 10.00%