Income Taxes - Components of provision (benefit) for income taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Oct. 03, 2020	Sep. 28, 2019	Sep. 29, 2018
Current:
U.S. Federal	$ (1,388)	$ 1,366	$ 0
U.S. State	724	1,132	177
Foreign	1,220	1,463	816
Total current	556	3,961	993
Deferred:
U.S. Federal	0	0	(168)
U.S. State	0	0	0
Foreign	(524)	(271)	231
Total deferred	(524)	(271)	63
Provision for income taxes	$ 32	$ 3,690	$ 1,056