Business - Additional Information (Details) - USD ($) $ in Thousands	Oct. 29, 2021	Sep. 30, 2021	Dec. 31, 2020
Cash and cash equivalents		$ 91,725	$ 115,069
Accumulated deficit		$ 831,058	$ 764,101
Common stock, shares authorized		350,000,000	350,000,000
Common stock, shares outstanding		216,145,804	214,591,906
Common Stock [Member]
Common stock, shares authorized		350,000,000
Common stock, shares outstanding	216,145,826
Common stock reserved for future issuance	33,778,465