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Stock-Based Compensation - Options Value Assumptions (Details) - Stock Options
3 Months Ended
Mar. 31, 2021
$ / shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Risk-free interest rate (percent) 0.50%
Weighted average historical volatility (percent) 67.70%
Dividend yield (percent) 0.00%
Expected years until exercise (years) 4 years 6 months
Weighted average fair value of options granted (USD per share) $ 39.85