Convertible Preferred Shares - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended		12 Months Ended
	Oct. 31, 2017	May 31, 2017	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Redeemable Noncontrolling Interest [Line Items]
Conversion of preferred stock to common stock (in shares)	24,425,190
Proceeds from issuance of convertible preferred shares			$ 0	$ 0	$ 52,300
Payments of convertible preferred share issuance costs			$ 0	$ 0	$ 429
Series C Convertible Preferred Shares
Redeemable Noncontrolling Interest [Line Items]
Number of convertible preferred shares sold under share purchase agreement (in shares)		690,333
Convertible preferred shares sold under share purchase agreement (in dollars per share)		$ 75.76
Proceeds from issuance of convertible preferred shares		$ 51,900
Payments of convertible preferred share issuance costs		$ 400