Note 10 - Earnings Per Share - Computation of Basic and Diluted Earnings Per Share (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 28, 2015	Jun. 29, 2014	Jun. 28, 2015	Jun. 29, 2014
Income from continuing operations	$ 7,669	$ 6,668	$ 18,437	$ 15,657
Income (loss) from discontinued operations, net of income taxes	(153)	236	(509)	111
Net income	$ 7,516	$ 6,904	$ 17,928	$ 15,768
Shares used in computing net income per common share:
Weighted average number of common shares outstanding - basic (in shares)	34,343,691	35,122,131	34,280,024	35,108,391
Weighted average number of common shares outstanding - diluted (in shares)	34,611,107	35,587,975	34,640,397	35,703,436
Basic earnings (loss) per common share:
Continuing operations (in dollars per share)	$ 0.22	$ 0.19	$ 0.53	$ 0.45
Discontinued operations (in dollars per share)	0	0.01	(0.01)	0
Basic earnings per common share (in dollars per share)	0.22	0.20	0.52	0.45
Diluted earnings (loss) per common share:
Continuing operations (in dollars per share)	0.22	0.18	0.53	0.44
Discontinued operations (in dollars per share)	0	0.01	(0.01)	0
Diluted earnings per common share (in dollars per share)	$ 0.22	$ 0.19	$ 0.52	$ 0.44