Taxes on Earnings - Schedule of Effective Income Tax Rate (Detail)	12 Months Ended
	Sep. 27, 2019	Sep. 28, 2018	Sep. 29, 2017
Income Tax Disclosure [Abstract]
Federal statutory income tax rate	21.00%	24.60%	35.00%
Impact of U.S. Tax Reform	2.10%	46.30%	0.00%
State and local taxes, net of federal tax benefit	2.60%	0.50%	0.90%
Non-U.S. income taxed at different rates, net	1.50%	(0.60%)	(8.40%)
Foreign-derived intangible income deduction	(1.40%)	0.00%	0.00%
Resolution of tax contingencies due to expiration of statutes of limitation	(1.80%)	(2.50%)	(1.70%)
Excess stock deduction	(1.60%)	(1.50%)	0.00%
Goodwill impairment	2.50%	0.00%	0.00%
Change in acquirer's deferred taxes related to purchase accounting	0.70%	(1.80%)	0.00%
In-process R&D expense	1.10%	0.00%	0.00%
Other	3.90%	1.80%	(0.40%)
Effective tax rate	30.60%	66.80%	25.40%