Leases (Maturity of Lease Liabilities) (Details) $ in Millions	Jul. 31, 2022 USD ($)
Operating Leases, Future Minimum Payments Due, Next Twelve Months	$ 66
Operating Leases, Future Minimum Payments, Due in Two Years	53
Operating Leases, Future Minimum Payments, Due in Three Years	40
Operating Leases, Future Minimum Payments, Due in Four Years	27
Operating Leases, Future Minimum Payments, Due in Five Years	22
Operating Leases, Future Minimum Payments, Due Thereafter	49
Operating Leases, Future Minimum Payments Due	257
Lessee, Operating Lease, Liability, Undiscounted Excess Amount	18
Operating Lease, Liability	239
Finance Lease, Liability, to be Paid, Year One	14
Finance Lease, Liability, to be Paid, Year Two	10
Finance Lease, Liability, to be Paid, Year Three	3
Finance Lease, Liability, to be Paid, Year Four	3
Finance Lease, Liability, to be Paid, Year Five	0
Finance Lease, Liability, to be Paid, after Year Five	0
Finance Lease, Liability, Payment, Due	30
Finance Lease, Liability, Undiscounted Excess Amount	0
Finance Lease, Liability	$ 30