Commitments (Details 2) - USD ($) $ in Millions	12 Months Ended
	Oct. 31, 2019	Oct. 31, 2018	Oct. 31, 2017
Lessee, Lease, Description [Line Items]
Rent expense	$ 283	$ 289	$ 290
Property under capital lease	61	61
Accumulated depreciation on property under capital lease	5,847	5,678
Assets Held under Capital Leases
Lessee, Lease, Description [Line Items]
Accumulated depreciation on property under capital lease	$ 13
Assets Held under Capital Leases
Lessee, Lease, Description [Line Items]
Accumulated depreciation on property under capital lease		$ 8