Restructuring (Details) $ in Millions	12 Months Ended
	Oct. 31, 2019 USD ($)	Oct. 31, 2018 USD ($) position	Oct. 31, 2017 USD ($)
Restructuring Reserve
Charges	$ 0	$ 19	$ 388
Short-term portion of restructuring reserve, recorded in Accrued restructuring	195	294
Long-term portion of restructuring reserve, recorded in Other liabilities	13	31
Restructuring Plan All
Restructuring Reserve
Balance at the beginning of the period	84	254	298
Charges		19	417
Cash payments	(38)	(181)	(412)
Non-cash items	(2)	(8)	(49)
Balance at the end of the period	44	84	254
Total costs incurred to date as of October 31, 2019	2,242
Total expected costs to be incurred as of October 31, 2019	2,242
Short-term portion of restructuring reserve, recorded in Accrued restructuring	31	53
Fiscal 2015 Plan
Restructuring Reserve
Total expected costs to be incurred as of October 31, 2019		$ 829
Expected positions to be eliminated | position		8,300
Fiscal 2015 Plan | Employee Severance
Restructuring Reserve
Balance at the beginning of the period	62	$ 219	234
Charges		9	374
Cash payments	(29)	(158)	(355)
Non-cash items	(2)	(8)	(34)
Balance at the end of the period	31	62	219
Total costs incurred to date as of October 31, 2019	751
Total expected costs to be incurred as of October 31, 2019	751	751
Fiscal 2015 Plan | Infrastructure and other
Restructuring Reserve
Balance at the beginning of the period	10	17	13
Charges		(2)	37
Cash payments	(3)	(8)	(19)
Non-cash items	0	3	(14)
Balance at the end of the period	7	10	17
Total costs incurred to date as of October 31, 2019	78
Total expected costs to be incurred as of October 31, 2019	78
Fiscal 2015 Plan | Real estate consolidation
Restructuring Reserve
Total expected costs to be incurred as of October 31, 2019		78
Fiscal 2012 Plan
Restructuring Reserve
Total costs incurred to date as of October 31, 2019		1,400
Fiscal 2012 Plan | Infrastructure and other
Restructuring Reserve
Balance at the beginning of the period	1	2	14
Charges		(1)	0
Cash payments	0	0	(6)
Non-cash items	(1)	0	(6)
Balance at the end of the period	0	1	2
Total costs incurred to date as of October 31, 2019	145
Total expected costs to be incurred as of October 31, 2019	145	145
Fiscal 2012 Plan | Employee Severance and EER
Restructuring Reserve
Balance at the beginning of the period	11	16	37
Charges		13	6
Cash payments	(6)	(15)	(32)
Non-cash items	1	(3)	5
Balance at the end of the period	6	11	16
Total costs incurred to date as of October 31, 2019	1,268
Total expected costs to be incurred as of October 31, 2019	$ 1,268	$ 1,300
Expected positions to be eliminated | position		10,300
Discontinued Operations
Restructuring Reserve
Charges			251
Restructuring charges
Restructuring Reserve
Charges			388
Non-Service Net Periodic Benefit Credit
Restructuring Reserve
Charges			$ 29