Note 6 - Acquisitions (Details Textual) - USD ($) $ in Thousands	9 Months Ended
	Oct. 03, 2015	Sep. 27, 2014
BGA [Member]
Business Combination, Contingent Consideration Arrangements, Range of Outcomes, Value, High	$ 2,600
PCI [Member]
Business Combination, Contingent Consideration Arrangements, Range of Outcomes, Value, High	2,000
SDS [Member]
Business Combination, Contingent Consideration Arrangements, Range of Outcomes, Value, High	1,500
Contingent Consideration [Member]
Payments to Acquire Businesses, Gross	100	$ 300
Payments to Acquire Businesses, Gross	$ 800