CONSOLIDATED STATEMENTS OF INCOME (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Share-based compensation expense	$ 2,458	$ 5,623	$ 3,796
Cost of revenues
Share-based compensation expense	72	203	466
Sales and marketing
Share-based compensation expense	92	442	134
Research, development and engineering
Share-based compensation expense	(19)	383	501
General and administrative
Share-based compensation expense	1,711	457	(16)
(Loss) income from discontinued operations
Share-based compensation expense	$ 602	$ 4,138	$ 2,711