Note 7 - Segment Information - Reconciliation of Segment Depreciation and Amortization (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 02, 2017	Jul. 03, 2016	Jul. 02, 2017	Jul. 03, 2016
Depreciation and amortization	$ 7,453	$ 7,443	$ 14,422	$ 14,960
Operating Segments [Member]
Depreciation and amortization	6,714	7,077	13,536	14,224
Corporate, Non-Segment [Member]
Depreciation and amortization	$ 739	$ 366	$ 886	$ 736