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Stock-Based Compensation and Employee Benefit Plans (ESPP Assumptions) (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Compensation costs related to shares not yet recognized $ 1.3    
Employee Stock      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Compensation costs related to shares not yet recognized $ 0.3    
Risk-free interest rate 1.84% 2.10% 1.17%
Expected term (years) 8 months 6 months 6 months
Expected volatility 42.00% 47.00% 37.00%