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Share-Based Compensation and Equity - Fair Value Assumptions (Details)
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Expected life (in years) 5 years 3 years 3 years
Weighted-average volatility 64.00% 62.00% 36.00%
Risk free interest rate, Minimum 0.49% 2.32% 2.39%
Risk free interest rate, Maximum 1.47% 2.58% 2.42%
Expected dividend yield 0.00% 0.00% 2.24%