Note 12 - Segment Information (Details) - Reconciliation of Certain Line Items Pertaining to Total Reportable Segments to Consolidated Financial Statements (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 28, 2014	Sep. 29, 2013	Sep. 28, 2014	Sep. 29, 2013
Note 12 - Segment Information (Details) - Reconciliation of Certain Line Items Pertaining to Total Reportable Segments to Consolidated Financial Statements [Line Items]
Operating income	$ 12,490	$ 8,975	$ 39,768	$ 32,305
Gain (loss) on sale of fixed assets	51	(6)	27	424
Unallocated corporate expenses	(2,473)	(1,824)	(7,807)	(7,235)
Amortization of intangible assets	(1,408)	(548)	(3,036)	(1,588)
Operating Segments [Member]
Note 12 - Segment Information (Details) - Reconciliation of Certain Line Items Pertaining to Total Reportable Segments to Consolidated Financial Statements [Line Items]
Operating income	$ 16,320	$ 11,353	$ 50,584	$ 40,704