Restructuring (Details) $ in Millions			3 Months Ended		9 Months Ended
	Aug. 20, 2015	Jul. 31, 2015 USD ($) position	Jul. 31, 2015 USD ($) position	Jul. 31, 2014 USD ($)	Jul. 31, 2015 USD ($) position	Jul. 31, 2014 USD ($)	Oct. 31, 2014 USD ($)
Restructuring Reserve
Balance at the beginning of the period					$ 1,114
Restructuring charges			$ 25	$ 649	426	$ 1,015
Cash Payments					(1,006)
Other Adjustments and Non-Cash Settlements					(78)
Balance at the end of the period		$ 456	456		456
Short-term portion of restructuring reserve, recorded in Accrued restructuring		330	330		330		$ 898
Long-term portion of restructuring reserve, recorded in Other liabilities		126	126		126		$ 216
Total Costs Incurred to Date		9,396	9,396		9,396
Total Expected Costs to be Incurred		9,548	9,548		9,548
Fiscal 2012 Restructuring Plan
Restructuring Reserve
Balance at the beginning of the period					1,053
Restructuring charges			32		440
Cash Payments					(994)
Other Adjustments and Non-Cash Settlements					(76)
Balance at the end of the period		423	423		423
Total Costs Incurred to Date		5,348	5,348		5,348
Total Expected Costs to be Incurred		5,500	5,500		$ 5,500
Completion Date					Oct. 31, 2021
Fiscal 2012 Restructuring Plan | Severance and EER
Restructuring Reserve
Balance at the beginning of the period					$ 955
Restructuring charges			14		385
Cash Payments					(898)
Other Adjustments and Non-Cash Settlements					(73)
Balance at the end of the period		369	369		369
Total Costs Incurred to Date		4,778	4,778		4,778
Total Expected Costs to be Incurred		$ 4,910	$ 4,910		$ 4,910
Expected positions to be eliminated | position		55,000
Positions eliminated | position		51,500	51,500		51,500
Fiscal 2012 Restructuring Plan | Severance and EER | Maximum
Restructuring Reserve
Additional positions to be eliminated (as a percent)	5.00%
Fiscal 2012 Restructuring Plan | Infrastructure and other items
Restructuring Reserve
Balance at the beginning of the period					$ 98
Restructuring charges			$ 18		55
Cash Payments					(96)
Other Adjustments and Non-Cash Settlements					(3)
Balance at the end of the period		$ 54	54		54
Total Costs Incurred to Date		570	570		570
Total Expected Costs to be Incurred		590	590		590
Other Plans
Restructuring Reserve
Balance at the beginning of the period					61
Restructuring charges			(7)		(14)
Cash Payments					(12)
Other Adjustments and Non-Cash Settlements					(2)
Balance at the end of the period		33	33		33
Total Costs Incurred to Date		4,048	4,048		4,048
Total Expected Costs to be Incurred		4,048	4,048		$ 4,048
Completion Date					Oct. 31, 2019
Other Plans | Severance and workforce reductions
Restructuring Reserve
Balance at the beginning of the period					$ 7
Restructuring charges			(4)		(4)
Other Adjustments and Non-Cash Settlements					(1)
Balance at the end of the period		2	2		2
Total Costs Incurred to Date		2,625	2,625		2,625
Total Expected Costs to be Incurred		2,625	2,625		2,625
Other Plans | Infrastructure
Restructuring Reserve
Balance at the beginning of the period					54
Restructuring charges			(3)		(10)
Cash Payments					(12)
Other Adjustments and Non-Cash Settlements					(1)
Balance at the end of the period		31	31		31
Total Costs Incurred to Date		1,423	1,423		1,423
Total Expected Costs to be Incurred		$ 1,423	$ 1,423		$ 1,423