Retirement Benefit Plans (Details) - Pension plans - USD ($) $ in Millions	3 Months Ended
	Oct. 30, 2020	Jul. 31, 2020	Jul. 26, 2019
U.S.
Net Periodic Benefit Cost
Service cost		$ 27	$ 26
Interest cost		27	32
Expected return on plan assets		(61)	(56)
Amortization of net actuarial loss		18	14
Net periodic benefit cost		11	16
U.S. | Subsequent Event | Forecast
Net Periodic Benefit Cost
Charge related to acceptance of voluntary early retirement packages	$ 100
Non-U.S.
Net Periodic Benefit Cost
Service cost		17	15
Interest cost		6	7
Expected return on plan assets		(14)	(15)
Amortization of net actuarial loss		6	3
Net periodic benefit cost		$ 15	$ 10