Note 4 - Restructuring Activities - Charges and Net Assets (Details) - USD ($) $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2022	Mar. 31, 2022	Jun. 30, 2021	Mar. 31, 2021	Jun. 30, 2022	Jun. 30, 2021	Dec. 31, 2021
Revenues	$ 6,368		$ 5,218		$ 11,903	$ 10,251
Net loss	(356)	$ (998)	(778)	$ 398	(1,354)	(380)
Total assets	49,118				49,118		$ 49,974
Total liabilities	4,535				4,535		3,774
CHINA
Revenues	0		4		1	15
Net loss	(38)		$ (63)		(51)	$ (38)
Total assets	1,121				1,121		1,235
Total liabilities	85				85		92
Total net assets	$ 1,036				$ 1,036		$ 1,143