Restructuring - Schedule of Restructuring Activities (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jul. 31, 2017	Jul. 31, 2016	Jul. 31, 2017	Jul. 31, 2016
Restructuring Reserve
Charges	$ 165	$ 93	$ 399	$ 346
Cash payments			(688)	$ (746)
Total
Restructuring Reserve
Beginning balance			353
Charges			399
Cash payments			(400)
Non-cash items			(62)
Ending balance	290		290
Total costs incurred to date, as of July 31, 2017	2,352		2,352
Total costs expected to be incurred, as of July 31, 2017	2,689		2,689
Fiscal 2012 Plan
Restructuring Reserve
Total costs incurred to date, as of July 31, 2017	1,400		1,400
Employee Severance | Fiscal 2015 Plan
Restructuring Reserve
Beginning balance			277
Charges			350
Cash payments			(351)
Non-cash items			(33)
Ending balance	243		243
Total costs incurred to date, as of July 31, 2017	794		794
Total costs expected to be incurred, as of July 31, 2017	982		982
Employee Severance | Fiscal 2012 Plan
Restructuring Reserve
Total costs incurred to date, as of July 31, 2017	1,200		1,200
Infrastructure and other | Fiscal 2015 Plan
Restructuring Reserve
Beginning balance			22
Charges			41
Cash payments			(18)
Non-cash items			(26)
Ending balance	19		19
Total costs incurred to date, as of July 31, 2017	99		99
Total costs expected to be incurred, as of July 31, 2017	248		248
Infrastructure and other | Fiscal 2012 Plan
Restructuring Reserve
Beginning balance			15
Charges			0
Cash payments			(5)
Non-cash items			(8)
Ending balance	2		2
Total costs incurred to date, as of July 31, 2017	222		222
Total costs expected to be incurred, as of July 31, 2017	222		222
Employee Severance and EER | Fiscal 2012 Plan
Restructuring Reserve
Beginning balance			39
Charges			8
Cash payments			(26)
Non-cash items			5
Ending balance	26		26
Total costs incurred to date, as of July 31, 2017	1,237		1,237
Total costs expected to be incurred, as of July 31, 2017	$ 1,237		$ 1,237