Annual report pursuant to Section 13 and 15(d)

Stockholders' Equity - Summary of Restricted Stock Activity (Details)

v3.20.4
Stockholders' Equity - Summary of Restricted Stock Activity (Details) - $ / shares
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Time based restricted stock units      
Class Of Stock [Line Items]      
Unvested restricted stock units/ awards outstanding, Beginning balance 108,976 58,589 42,028
Granted 210,622 87,902 31,877
Vested (49,636) (24,680) (13,742)
Forfeited/canceled (24,500) (12,835) (1,574)
Unvested restricted stock units/ awards outstanding, Ending balance 245,462 108,976 58,589
Performance and time based restricted stock units      
Class Of Stock [Line Items]      
Unvested restricted stock units/ awards outstanding, Beginning balance 3,134 8,739 13,109
Granted 88,458    
Vested   (4,366) (4,370)
Forfeited/canceled (3,134) (1,239)  
Unvested restricted stock units/ awards outstanding, Ending balance 88,458 3,134 8,739
Restricted stock units      
Class Of Stock [Line Items]      
Unvested restricted stock units/ awards outstanding, Beginning balance 112,110 67,328 55,137
Granted 299,080 87,902 31,877
Vested (49,636) (29,046) (18,112)
Forfeited/canceled (27,634) (14,074) (1,574)
Unvested restricted stock units/ awards outstanding, Ending balance 333,920 112,110 67,328
Unvested and expected to vest restricted stock units/awards outstanding 246,420 103,087 62,504
Weighted-average grant date fair value per share, Unvested restricted stock units/ awards outstanding, Beginning balance $ 83.48 $ 115.16 $ 90.05
Weighted-average grant date fair value per share, Granted 43.52 75.56 143.50
Weighted-average grant date fair value per share, Vested 83.31 123.53 89.35
Weighted-average grant date fair value per share, Forfeited/canceled 70.60 102.89 106.55
Weighted-average grant date fair value per share, Unvested restricted stock units/ awards outstanding, Ending balance 49.29 83.48 115.16
Weighted-average grant date fair value per share, Unvested and expected to vest restricted stock units/awards outstanding $ 49.82 $ 83.22 $ 115.98
Time based restricted stock awards      
Class Of Stock [Line Items]      
Unvested restricted stock units/ awards outstanding, Beginning balance 71,070 36,937 20,789
Granted   54,853 22,645
Vested (28,994) (13,627) (6,497)
Forfeited/canceled   (7,093)  
Unvested restricted stock units/ awards outstanding, Ending balance 42,076 71,070 36,937
Performance and time based restricted stock awards      
Class Of Stock [Line Items]      
Unvested restricted stock units/ awards outstanding, Beginning balance 62,628 47,821 20,785
Granted   40,166 33,964
Vested   (15,732) (6,928)
Forfeited/canceled (29,273) (9,627)  
Unvested restricted stock units/ awards outstanding, Ending balance 33,355 62,628 47,821
Restricted stock awards      
Class Of Stock [Line Items]      
Unvested restricted stock units/ awards outstanding, Beginning balance 133,698 84,758 41,574
Granted   95,019 56,609
Vested (28,994) (29,359) (13,425)
Forfeited/canceled (29,273) (16,720)  
Unvested restricted stock units/ awards outstanding, Ending balance 75,431 133,698 84,758
Unvested and expected to vest restricted stock units/awards outstanding 44,159 79,473 65,773
Weighted-average grant date fair value per share, Unvested restricted stock units/ awards outstanding, Beginning balance $ 95.74 $ 115.80 $ 91.52
Weighted-average grant date fair value per share, Granted   86.10 130.89
Weighted-average grant date fair value per share, Vested 89.37 115.37 91.52
Weighted-average grant date fair value per share, Forfeited/canceled 110.27 109.11  
Weighted-average grant date fair value per share, Unvested restricted stock units/ awards outstanding, Ending balance 93.96 95.74 115.80
Weighted-average grant date fair value per share, Unvested and expected to vest restricted stock units/awards outstanding $ 85.90 $ 90.31 $ 115.85