Note 3 - Goodwill and Other Purchased Intangible Assets - Purchased Intangible Assets, Subject to Amortization (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 27, 2015	Dec. 27, 2014
Rasco Technology [Member]
Intangible assets, gross	$ 27,372	$ 29,845
Intangible assets, accumulated amortization	$ 22,479	22,616
Intangible assets, useful life	1 year 182 days
Ismeca Technology [Member]
Intangible assets, gross	$ 28,575	27,014
Intangible assets, accumulated amortization	$ 9,095	6,879
Intangible assets, useful life	5 years 182 days
Intangible assets, gross	$ 55,947	56,859
Intangible assets, accumulated amortization	$ 31,574	$ 29,495