Income taxes - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income Tax [Line Items]
Loss before income taxes	$ 33,399,000	$ (5,393,000)
Income Tax Expense (Benefit)	1,140,000	(185,000)
Operating Loss Carryforwards	$ 29,300,000
Percentage of tax earnings	80.00%
Deferred Tax Assets, Valuation Allowance	$ 15,149,000	$ 19,033,000	$ 19,000,000.0	$ 11,300,000
Reduction in valuation allowance	3,900,000
Net Operating Loss Due to additional income	16,800,000
No Expiration [Member]
Income Tax [Line Items]
Operating Loss Carryforwards	0
State and Local Jurisdiction [Member]
Income Tax [Line Items]
Operating Loss Carryforwards	$ 21,000,000.0