Commitments (Details) - USD ($) $ in Millions	12 Months Ended
	Oct. 31, 2018	Oct. 31, 2017	Oct. 31, 2016
Commitments and Contingencies Disclosure [Abstract]
Rent expense	$ 289	$ 290	$ 307
Property under capital lease	61	75
Accumulated depreciation on property under capital lease	8	$ 16
Operating lease commitments, sublease rental income
2019	226
2020	207
2021	152
2022	131
2023	116
Thereafter	387
Less: Sublease rental income	(216)
Total	1,003
Unconditional purchase obligations	600
Unconditional purchase obligations details
2019	257
2020	196
2021	110
2022	16
2023	9
Thereafter	49
Total	$ 637