Earnings per share - Schedule of Computation of Basic and Diluted Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2021	Sep. 30, 2020
Numerator for basic and diluted loss per share
Net loss	$ (549)	$ (1,483)	$ (2,062)	$ (1,117)	$ (2,166)	$ (4,596)	$ (4,094)	$ (7,879)
Weighted average number of shares outstanding - basic (in shares)	62,610			49,651			56,280	43,074
Weighted average number of shares outstanding - diluted (in shares)	62,610			49,651			56,280	43,074
Net income/(loss) per share
Basic (in dollars per share)	$ (0.01)			$ (0.02)			$ (0.07)	$ (0.18)
Diluted (in dollars per share)	$ (0.01)			$ (0.02)			$ (0.07)	$ (0.18)