Note 1 - Summary of Significant Accounting Policies - Schedule of Reported Share-based Compensation in Condensed Consolidated Interim Financial Statements (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 26, 2015	Sep. 27, 2014	Sep. 26, 2015	Sep. 27, 2014
Cost of Sales [Member]
Allocated share-based compensation	$ 100	$ 85	$ 413	$ 350
Research and Development Expense [Member]
Allocated share-based compensation	256	453	841	1,364
Selling, General and Administrative Expenses [Member]
Allocated share-based compensation	1,281	1,047	3,827	2,919
Allocated share-based compensation	1,637	1,585	5,081	4,633
Income tax benefit	(70)	(60)	(181)	(157)
Total share-based compensation, net	$ 1,567	$ 1,525	$ 4,900	$ 4,476