Restructuring (Details) $ in Millions		12 Months Ended
	Sep. 14, 2015 USD ($) employee	Oct. 31, 2015 USD ($) position	Oct. 31, 2014 USD ($)	Oct. 31, 2013 USD ($)
Restructuring Reserve
Balance at the beginning of the period		$ 1,114
Restructuring charges		1,017	$ 1,619	$ 990
Cash Payments		(1,243)
Other Adjustments and Non-Cash Settlements		(83)
Balance at the end of the period		805	1,114
Short-term portion of restructuring reserve, recorded in Accrued restructuring		689	898
Long-term portion of restructuring reserve, recorded in Other liabilities		116	216
Total Costs Incurred to Date		9,988
Total Expected Costs to be Incurred		12,458
Fiscal 2015 Restructuring Plan
Restructuring Reserve
Restructuring charges		391
Cash Payments		(1)
Balance at the end of the period		390
Total Costs Incurred to Date		391
Total Expected Costs to be Incurred	$ 2,900	$ 2,861
Completion Date		Oct. 31, 2018
Fiscal 2015 Restructuring Plan | Maximum
Restructuring Reserve
Expected positions to be eliminated | employee	33,300
Fiscal 2015 Restructuring Plan | Parent Company
Restructuring Reserve
Total Expected Costs to be Incurred	$ 280
Fiscal 2015 Restructuring Plan | Severance
Restructuring Reserve
Restructuring charges		$ 390
Balance at the end of the period		390
Total Costs Incurred to Date		390
Total Expected Costs to be Incurred		2,355
Fiscal 2015 Restructuring Plan | Infrastructure and other items
Restructuring Reserve
Restructuring charges		1
Cash Payments		(1)
Total Costs Incurred to Date		1
Total Expected Costs to be Incurred	506	506
Fiscal 2015 Restructuring Plan | Severance and workforce reductions
Restructuring Reserve
Total Expected Costs to be Incurred	$ 2,400
Fiscal 2012 Restructuring Plan
Restructuring Reserve
Balance at the beginning of the period		1,053
Restructuring charges		640
Cash Payments		(1,221)
Other Adjustments and Non-Cash Settlements		(82)
Balance at the end of the period		390	1,053
Total Costs Incurred to Date		5,548
Total Expected Costs to be Incurred		$ 5,548
Completion Date		Oct. 31, 2021
Fiscal 2012 Restructuring Plan | Severance
Restructuring Reserve
Balance at the beginning of the period		$ 955
Restructuring charges		566
Cash Payments		(1,101)
Other Adjustments and Non-Cash Settlements		(78)
Balance at the end of the period		342	955
Total Costs Incurred to Date		4,959
Total Expected Costs to be Incurred		$ 4,959
Expected positions to be eliminated | position		55,800
Fiscal 2012 Restructuring Plan | Infrastructure and other items
Restructuring Reserve
Balance at the beginning of the period		$ 98
Restructuring charges		74
Cash Payments		(120)
Other Adjustments and Non-Cash Settlements		(4)
Balance at the end of the period		48	98
Total Costs Incurred to Date		589
Total Expected Costs to be Incurred		589
Other Plans
Restructuring Reserve
Balance at the beginning of the period		61
Restructuring charges		(14)
Cash Payments		(21)
Other Adjustments and Non-Cash Settlements		(1)
Balance at the end of the period		25	61
Total Costs Incurred to Date		4,049
Total Expected Costs to be Incurred		$ 4,049
Completion Date		Oct. 31, 2019
Other Plans | Severance and workforce reductions
Restructuring Reserve
Balance at the beginning of the period		$ 7
Restructuring charges		(4)
Cash Payments		(1)
Other Adjustments and Non-Cash Settlements		(1)
Balance at the end of the period		1	7
Total Costs Incurred to Date		2,625
Total Expected Costs to be Incurred		2,625
Other Plans | Infrastructure
Restructuring Reserve
Balance at the beginning of the period		54
Restructuring charges		(10)
Cash Payments		(20)
Balance at the end of the period		24	$ 54
Total Costs Incurred to Date		1,424
Total Expected Costs to be Incurred		$ 1,424