Note 1 - Nature of Operations (Details Textual) $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2020 USD ($)	Jun. 30, 2020 USD ($)	Mar. 31, 2020 USD ($)	Sep. 30, 2019 USD ($)	Jun. 30, 2019 USD ($)	Mar. 31, 2019 USD ($)	Sep. 30, 2020 USD ($)	Sep. 30, 2019 USD ($)	Apr. 10, 2020 USD ($)
Number of Operating Segments							2
Net Income (Loss) Attributable to Parent, Total	$ 458	$ 170	$ (1,143)	$ 647	$ (187)	$ 1,138	$ (515)	$ 1,598
Revenue from Contract with Customer, Including Assessed Tax	14,443			14,632			38,948	47,046
M&T [Member] | Revolving Credit Facility [Member]
Line of Credit Facility, Maximum Borrowing Capacity									$ 7,500
Semiconductor Market [Member]
Revenue from Contract with Customer, Including Assessed Tax	$ 7,387			$ 7,126			$ 19,256	$ 24,878