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Restructuring (Details) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
Restructuring (Details) $ in Thousands	Mar. 29, 2019 USD ($)	Mar. 30, 2018 USD ($)	Mar. 29, 2019 USD ($)	Mar. 30, 2018 USD ($)	Sep. 29, 2017 USD ($) employee
Restructuring Reserve [Roll Forward]
Restructuring charges	$ (18)	$ 167	$ (32)	$ 364
2017 Restructuring Plan [Member] [Member]
Restructuring Cost and Reserve [Line Items]
Number of positions eliminated \| employee					80
Restructuring Reserve [Roll Forward]
Restructuring reserve, beginning balance			124
Restructuring charges			0		$ (12,900)
Cash payments			(98)
Non-cash charges			(63)
Restructuring reserve, ending balance	$ 89		$ 89