Stockholders' equity - Common stock (Details) - shares	Mar. 31, 2022	Dec. 31, 2021
Class of Stock [Line Items]
Common stock, shares authorized (in shares)	110,000,000	110,000,000
Common stock, shares outstanding (in shares)	67,056,826	66,850,941
Common Stock
Class of Stock [Line Items]
Common stock, shares authorized (in shares)	110,000,000
Common stock, shares outstanding (in shares)	67,100,000	66,900,000