Note 6 - Acquisitions - Proforma Revenue and Earnings (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 28, 2019	Sep. 29, 2018	Sep. 28, 2019	Sep. 29, 2018
Revenue	$ 40,250	$ 42,559	$ 142,550	$ 145,081
Operating income	$ 731	$ 1,232	$ 4,579	$ 3,842
Diluted net income per share (in dollars per share)		$ 0.06		$ 0.17
TKE [Member]
Revenue		$ 44,352		$ 150,161
Operating income		$ 1,538		$ 4,760
Diluted net income per share (in dollars per share)		$ 0.07		$ 0.22