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Business Segment Data (Details)
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Business Segment Data (Details) [Line Items]    
Number of Reportable Segments 2  
Foreign [Member] | Revenue Benchmark [Member]    
Business Segment Data (Details) [Line Items]    
Concentration Risk, Percentage 10.00% 10.00%