Leases - Additional Information (Details) $ in Millions	3 Months Ended	6 Months Ended
	Mar. 28, 2020 USD ($)	Mar. 28, 2020 USD ($)
Lessee, Lease, Description [Line Items]
Typical term of leases (not exceeding)		10 years
Fixed operating lease costs	$ 363	$ 732
Variable lease costs	1,900	4,800
Operating lease payments	353	702
Right-of-use assets obtained in exchange for operating and finance lease liabilities	$ 1,200	$ 9,300
Weighted-average remaining lease term		10 years 8 months 12 days
Weighted-average discount rate	2.20%	2.20%
Leases not yet commenced, future payments	$ 1,800	$ 1,800
Minimum
Lessee, Lease, Description [Line Items]
Leases not yet commenced, lease term	1 year	1 year
Maximum
Lessee, Lease, Description [Line Items]
Leases not yet commenced, lease term	21 years	21 years