Retirement Plans - Defined Benefit Pension Plan Costs (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 27, 2019	Sep. 28, 2018	Sep. 29, 2017
Non-U.S. Plans
Operating expense:
Service cost	$ 47	$ 46	$ 50
Other (income) expense:
Interest cost	42	42	35
Expected return on plan assets	(64)	(69)	(68)
Amortization of net actuarial loss	24	24	41
Amortization of prior service credit and other	(8)	(6)	(4)
Net periodic pension benefit cost	$ 41	$ 37	$ 54
Weighted average assumptions used to determine net pension benefit cost during the fiscal year:
Discount rate (as a percent)	1.94%	1.87%	1.44%
Expected return on plan assets (as a percent)	4.65%	4.92%	5.21%
Rate of compensation increase (as a percent)	2.57%	2.53%	2.52%
U.S. Plans
Operating expense:
Service cost	$ 13	$ 14	$ 12
Other (income) expense:
Interest cost	46	43	43
Expected return on plan assets	(58)	(59)	(53)
Amortization of net actuarial loss	17	22	40
Net periodic pension benefit cost	$ 18	$ 20	$ 42
Weighted average assumptions used to determine net pension benefit cost during the fiscal year:
Discount rate (as a percent)	4.35%	3.77%	3.58%
Expected return on plan assets (as a percent)	6.57%	6.45%	5.93%