Organization and description of business - Additional Information (Details) - USD ($) $ in Thousands	1 Months Ended	6 Months Ended
	Dec. 31, 2020	Jun. 30, 2022	Dec. 31, 2021
Organization And Description Of Business [Line Items]
Date of incorporation		Nov. 19, 2012
Accumulated deficit		$ (346,103)	$ (316,102)
Open Market Sale Agreement
Organization And Description Of Business [Line Items]
Number of shares sold		300,000
Net proceeds from common stock		$ 1,100
Proceeds from issuance of remaining common stock		$ 40,600
Open Market Sale Agreement | Jefferies LLC
Organization And Description Of Business [Line Items]
Maximum Offering Issuance And Sale Expense Covered In Company Securities	$ 200,000
Maximum Aggregate Offering Price	$ 50,000