Restructuring and Other Charges - Summary of Restructuring Plans (Details) - USD ($) $ in Millions	12 Months Ended
	Oct. 31, 2020	Oct. 31, 2019	Oct. 31, 2018	Oct. 31, 2020
Restructuring Reserve [Roll Forward]
Accrued balance, beginning of period	$ 142	$ 59	$ 108
Charges	357	247	99
Cash payments	(381)	(140)	(175)
Non-cash and other adjustments	(51)	(24)	27
Accrued balance, end of period	67	142	59
Total costs incurred to date				$ 2,255
Accrued balance	67	142	59	67
Other current liabilities
Restructuring Reserve [Roll Forward]
Accrued balance, end of period	67
Accrued balance	67			67
Fiscal 2020 Plan | Severance and EER
Restructuring Reserve [Roll Forward]
Accrued balance, beginning of period	76	0	0
Charges	346	82	0
Cash payments	(319)	0	0
Non-cash and other adjustments	(48)	(6)	0
Accrued balance, end of period	55	76	0
Total costs incurred to date				428
Accrued balance	55	76	0	55
Fiscal 2020 Plan | Severance and EER | Other current liabilities
Restructuring Reserve [Roll Forward]
Accrued balance, end of period	55
Accrued balance	55			55
Fiscal 2020 Plan | Non-labor
Restructuring Reserve [Roll Forward]
Accrued balance, beginning of period	0	0	0
Charges	10	0	0
Cash payments	(10)	0	0
Non-cash and other adjustments	0	0	0
Accrued balance, end of period	0	0	0
Total costs incurred to date				10
Accrued balance	0	0	0	0
Fiscal 2020 Plan | Non-labor | Other current liabilities
Restructuring Reserve [Roll Forward]
Accrued balance, end of period	0
Accrued balance	0			0
Fiscal 2020 Plan | EER
Restructuring Reserve [Roll Forward]
Non-cash and other adjustments	(44)
Other prior year plans
Restructuring Reserve [Roll Forward]
Accrued balance, beginning of period	66	59	108
Charges	1	165	99
Cash payments	(52)	(140)	(175)
Non-cash and other adjustments	(3)	(18)	27
Accrued balance, end of period	12	66	59
Total costs incurred to date				1,817
Accrued balance	12	$ 66	$ 59	12
Other prior year plans | Other current liabilities
Restructuring Reserve [Roll Forward]
Accrued balance, end of period	12
Accrued balance	$ 12			$ 12