Accrued Liabilities - Schedule of Accrued Liabilities (Detail) - USD ($) $ in Thousands	Oct. 02, 2020	Sep. 27, 2019
Other Liabilities Disclosure [Abstract]
Compensation and benefits	$ 32,254	$ 20,455
Distribution costs	8,889	7,797
Deferred revenue	6,346	2,137
Product warranty	1,858	3,273
Restructuring costs	261	2,527
Professional fees	1,300	1,554
Rent and utilities	589	701
Income taxes payable	734	1,233
Current portion of operating leases	7,601	0
Other	3,822	2,368
Total accrued liabilities	$ 63,654	$ 42,045
Operating Lease, Liability, Current, Statement of Financial Position [Extensible List]	us-gaap:AccruedLiabilitiesCurrent	us-gaap:AccruedLiabilitiesCurrent