Leases - Operating Lease Balances (Details) - USD ($) $ in Millions	Apr. 30, 2022	Jul. 31, 2021
Leases [Abstract]
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration]	Other assets	Other assets
Operating lease right-of-use assets	$ 1,024	$ 1,095
Operating Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]	Other current liabilities	Other current liabilities
Operating lease liabilities	$ 334	$ 337
Operating Lease, Liability, Noncurrent, Statement of Financial Position [Extensible Enumeration]	Other long-term liabilities	Other long-term liabilities
Operating lease liabilities	$ 739	$ 831
Total operating lease liabilities	$ 1,073	$ 1,168