Annual report pursuant to Section 13 and 15(d)

Share-Based Compensation - Summary of Restricted Ordinary Share Activity and Related Information (Details)

v3.19.1
Share-Based Compensation - Summary of Restricted Ordinary Share Activity and Related Information (Details) - Restricted Ordinary Shares - $ / shares
12 Months Ended
Dec. 31, 2018
Dec. 31, 2017
Number of Shares    
Number of Shares, Unvested, Beginning balance 189,342 292,620
Number of Shares, Vested (103,274) (103,278)
Number of Shares, Unvested, Ending balance 86,068 189,342
Weighted Average grant date fair value per share    
Weighted Average grant date fair value per share, Unvested, Beginning balance $ 3.14 $ 3.14
Weighted Average grant date fair value per share, Vested 3.14 3.14
Weighted Average grant date fair value per share, Unvested, Ending balance $ 3.14 $ 3.14