Restructuring (Details) $ in Millions	3 Months Ended	6 Months Ended
	Apr. 30, 2016 USD ($)	Apr. 30, 2016 USD ($) item	Apr. 30, 2015 USD ($)	Sep. 14, 2015 USD ($)
Restructuring Reserve
Charges		$ 120	$ 401
Fiscal 2015 Plan
Restructuring Reserve
Balance at the beginning of the period		39
Charges	$ 98	118
Cash Payments		(43)
Non-Cash and Other Adjustments		(39)
Balance at the end of the period	75	75
Total Costs Incurred to Date	156	156
Total Expected Costs to be Incurred	300	$ 300
Expected positions to be eliminated | item		3,000
Completion Date		Oct. 31, 2016
Fiscal 2015 Plan | Maximum
Restructuring Reserve
Total Expected Costs to be Incurred				$ 300
Fiscal 2015 Plan | Severance and PRP
Restructuring Reserve
Balance at the beginning of the period		$ 39
Charges	72	87
Cash Payments		(42)
Non-Cash and Other Adjustments		(10)
Balance at the end of the period	74	74
Total Costs Incurred to Date	125	125
Total Expected Costs to be Incurred	240	240
Fiscal 2015 Plan | Infrastructure and other
Restructuring Reserve
Charges	26	31
Cash Payments		(1)
Non-Cash and Other Adjustments		(29)
Balance at the end of the period	1	1
Total Costs Incurred to Date	31	31
Total Expected Costs to be Incurred	60	60
Voluntary Phased Retirement Program ("PRP")
Restructuring Reserve
Charges	29	29
Fiscal 2012 Plan
Restructuring Reserve
Balance at the end of the period	11	11
Total severance charges	$ 2	$ 2
Completion Date		Oct. 31, 2021