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Stock-Based Awards - Summary of Restricted Stock Activity (Details) - Restricted Stock - $ / shares
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Share Awards & Units    
Shares, unvested, beginning balance (in shares) 503,243  
Shares, granted (in shares) 850,234  
Shares, vested (in shares) (419,064)  
Shares, forfeited (in shares) (51,777)  
Shares, unvested, ending balance (in shares) 882,636 503,243
Shares, vested and expected to vest (in shares) 882,636  
Weighted-Average Fair Value at Date of Grant per Share    
Weighted-average fair value at date of grant per share, unvested, beginning balance (usd per share) $ 4.86  
Weighted-average fair value at date of grant per share, granted (usd per share) 18.86 $ 15.92
Weighted-average fair value at date of grant per share, vested (usd per share) 2.63  
Weighted-average fair value at date of grant per share, forfeited (usd per share) 20.50  
Weighted-average fair value at date of grant per share, unvested, ending balance (usd per share) 18.67 $ 4.86
Weighted-average fair value at date of grant per share, vested and expected to vest (usd per share) $ 18.67