Note 4 - Restructuring Activities - Charges and Net Assets (Details) - USD ($) $ 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	Dec. 31, 2020
Revenues	$ 7,559			$ 8,155			$ 17,810	$ 16,334
Net loss	678	$ (778)	$ 398	2,376	$ (2,544)	$ (2,567)	298	(2,735)
Total assets	51,039						51,039		$ 30,088
Total liabilities	4,595						4,595		7,767
CHINA
Revenues	2			6			17	11
Net loss	(47)			$ (73)			(85)	$ (31)
Total assets	1,444						1,444		2,463
Total liabilities	290						290		396
Total net assets	$ 1,154						$ 1,154		$ 2,067