Summary of significant accounting policies - Trade Receivables, net (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Balance, beginning of period	$ 492	$ 603	$ 391	$ 530
Provision	140	(100)	262	56
Write-offs	(155)	(45)	(182)	(172)
Recoveries of amounts previously written off	2	22	8	66
Balance, end of period	$ 479	$ 480	$ 479	$ 480