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Stock-based Compensation - Summary of Restricted Common Stock (Details) - Restricted Common Stock - $ / shares
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Shares    
Number of Shares, Unvested, beginning balance 994,838 1,917,848
Number of Shares, Vested (726,659) (866,037)
Number of Shares, Forfeited (81,754) (56,973)
Number of Shares, Unvested, ending balance 186,425 994,838
Weighted-average grant-date fair value    
Weighted Average Grant Date Fair Value per Share, Unvested, beginning balance $ 6.95 $ 6.95
Weighted Average Grant Date Fair Value per Share, Vested 6.95 6.95
Weighted Average Grant Date Fair Value per Share, Forfeited 6.95 6.95
Weighted Average Grant Date Fair Value per Share, Unvested, ending balanc $ 6.95 $ 6.95