Note 2 - Business Acquisitions, Goodwill and Purchased Intangible Assets - Fair Value of Contingent Consideration (Details) - USD ($) $ in Thousands		9 Months Ended		12 Months Ended
	Jan. 04, 2017	Sep. 29, 2018	Sep. 30, 2017	Dec. 30, 2017
Mark-to-market adjustments charged to expense		$ 657	$ 668
Kita Manufacturing Co. LTD. and Kita USA, Inc. [Member]
Balance for contingent consideration		2,253
Fair value of contingent consideration	$ 823			823
Mark-to-market adjustments charged to expense		657		1,423
Impact of currency exchange		60		7
Settlement of contingent consideration		(1,500)
Balance for contingent consideration		$ 1,470		$ 2,253