Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Millions	3 Months Ended
	Apr. 30, 2022	Apr. 30, 2021
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning balance	$ 91,891	$ 87,531
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	251	(259)
Reclassifications related to business dispositions		4,059
Reclassifications to income, net	17	20
Ending balance	85,600	84,592
AOCI Including Portion Attributable to Noncontrolling Interest
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning balance	(8,766)	(11,766)
Ending balance	(8,498)	(7,946)
Currency  Translation and Other
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning balance	(8,100)	(10,772)
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	225	(225)
Reclassifications related to business dispositions		3,258
Reclassifications to income, net	0	0
Ending balance	(7,875)	(7,739)
Net Investment Hedges
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning balance	94	1,296
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	0	(7)
Reclassifications related to business dispositions		(1,195)
Reclassifications to income, net	0	0
Ending balance	94	94
Cash Flow Hedges
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning balance	(748)	(304)
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	26	(26)
Reclassifications related to business dispositions		30
Reclassifications to income, net	16	16
Ending balance	(706)	(284)
Minimum Pension  Liability
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning balance	(12)	(1,986)
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	0	(1)
Reclassifications related to business dispositions		1,966
Reclassifications to income, net	1	4
Ending balance	$ (11)	$ (17)