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Stockholders' Equity (Schedule of Fair Value of Option Grant Estimated Using Black-Scholes Option Pricing Model) (Details)
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Annual dividend
Risk free interest rate, minimum 0.30%  
Risk free interest rate, maximum 0.50%  
Expected volatility, minimum 40.90%  
Expected volatility, maximum 46.60%  
Minimum [Member]    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Expected life (in years) 5 years 2 months 30 days  
Maximum [Member]    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Expected life (in years) 6 years 2 months 30 days