Retirement Plans (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jun. 26, 2020	Jun. 28, 2019	Jun. 26, 2020	Jun. 28, 2019
Non-U.S. Plans
Net Periodic Postretirement Benefit Cost (Credit)
Service cost	$ 13	$ 12	$ 38	$ 36
Interest cost	6	11	18	32
Expected return on plan assets	(15)	(16)	(45)	(48)
Amortization of net actuarial loss	10	6	30	18
Amortization of prior service credit	(1)	(2)	(4)	(6)
Net periodic pension benefit cost (credit)	13	11	37	32
Defined benefit plan, contributions by employer			29
U.S. Plans
Net Periodic Postretirement Benefit Cost (Credit)
Service cost	2	4	7	10
Interest cost	9	11	27	34
Expected return on plan assets	(15)	(14)	(44)	(43)
Amortization of net actuarial loss	3	4	7	13
Net periodic pension benefit cost (credit)	$ (1)	$ 5	$ (3)	$ 14