Note 10 - Income Taxes - Components of Income Tax Expense Benefit (Details) - USD ($) $ in Thousands	12 Months Ended
	Jan. 03, 2021	Dec. 29, 2019	Dec. 30, 2018
Income (loss) before income taxes	$ (11,100)	$ (15,524)	$ (13,627)
Federal	0	0	(19)
State	3	3	2
Foreign	39	108	169
Subtotal	42	111	152
Federal	0	(141)	0
State	0	(44)	0
Foreign	9	(6)	0
Subtotal	9	(191)	0
Provision for (benefit from) income taxes	51	(80)	152
Domestic Tax Authority [Member]
U.S.	(11,170)	(15,813)	(13,982)
Foreign Tax Authority [Member]
Foreign	$ 70	$ 289	$ 355