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Share-Based Compensation (Schedule of Assumptions Used to Determine Fair Value of Stock Options Granted) (Details) - Employee Stock Option [Member]
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Risk-free interest rate, minimum 1.41% 2.63% 1.92%
Risk-free interest rate, maximum 2.56% 3.10% 2.29%
Dividend yield 0.00% 0.00% 0.00%
Expected market price volatility, minimum 47.00% 45.00% 45.00%
Expected market price volatility, maximum 52.00% 52.00% 53.00%
Weighted-average expected market price volatility 49.40% 49.10% 47.40%
Minimum [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Expected term 4 years 7 months 6 days 4 years 8 months 12 days 5 years 7 months 6 days
Maximum [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Expected term 6 years 6 months 6 years 9 months 18 days 7 years 6 months