Note 13 - 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. 29, 2013	Sep. 30, 2012	Sep. 30, 2012	Sep. 29, 2013	Sep. 30, 2012
Reconciliation of certain line items pertaining to total reportable segments to consolidated financial statements [Abstract]
Operating income for reportable segments	$ 11,353		$ 8,868	$ 40,704	$ 28,356
Corporate incentive agreements	29		121	73	211
(Gain) loss on sale of fixed assets and acquisition of business	(6)	234	234	424	237
Unallocated corporate expenses	(1,853)		(1,570)	(7,308)	(5,388)
Amortization of intangible assets	(548)	(342)	(342)	(1,588)	(992)
Consolidated operating income	$ 8,975	$ 7,311	$ 7,311	$ 32,305	$ 22,424