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Note 3 - Business Combination - Restructuring Activity (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended	9 Months Ended
	Jun. 27, 2020	Jun. 29, 2019	Mar. 28, 2020	Jun. 27, 2020	Jun. 29, 2019
Restructuring charges	$ 808	$ 0	$ 149	$ 957	$ 0
Cash payments	(490)		(4)
Liability balance	120		145	120
Non-cash charges	(343)
Employee Severance [Member]
Restructuring charges	76		129
Cash payments	(124)		(4)
Liability balance	77		125	77
Non-cash charges	0
Equipment Relocation [Member]
Restructuring charges	16		0
Cash payments	(16)		0
Liability balance	0		0	0
Non-cash charges	0
Facility Closing [Member]
Restructuring charges	373		20
Cash payments	(350)		0
Liability balance	43		20	43
Non-cash charges	0
Asset Impairments [Member]
Restructuring charges	343		0
Cash payments	0		0
Liability balance	0		$ 0	$ 0
Non-cash charges	$ (343)