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Stock-Based Compensation Expense - Schedule of Assumptions Used to Value Options Granted (Details) - Employee stock purchase plan
1 Months Ended
Feb. 29, 2020
Feb. 28, 2019
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology [Abstract]    
Expected life (in years) 2 years 2 years
Risk-free interest rate 1.40% 2.50%
Dividend yield 4.00% 5.40%
Expected volatility 45.80% 53.40%