Note 6 - Acquisitions (Details Textual) - USD ($) $ in Thousands	3 Months Ended
	Apr. 02, 2016	Apr. 04, 2015
BGA [Member]
Business Combination, Contingent Consideration Arrangements, Range of Outcomes, Value, High	$ 1,900
PCI [Member]
Business Combination, Contingent Consideration Arrangements, Range of Outcomes, Value, High	1,900
SDS [Member]
Business Combination, Contingent Consideration Arrangements, Range of Outcomes, Value, High	1,500
Contingent Consideration [Member]
Payments to Acquire Businesses, Gross	$ 35	$ 90