Short-term Borrowings and Long-term Debt - Schedule of Long-term Debt (Details) - USD ($) $ in Millions	Jan. 31, 2025	Jan. 31, 2024
Debt Instrument [Line Items]
Unsecured debt	$ 36,846	$ 40,405
Total debt	35,999	39,579
Less amounts due within one year	(2,598)	(3,447)
Long-term debt	33,401	36,132
Unsecured fixed-rate debt
Debt Instrument [Line Items]
Total debt	35,999
Total other debt
Debt Instrument [Line Items]
Total other	(847)	(826)
Denominated US Dollar with Fixed Rate
Debt Instrument [Line Items]
Unsecured debt	$ 31,406	$ 34,527
Denominated US Dollar with Fixed Rate | Unsecured fixed-rate debt
Debt Instrument [Line Items]
Average Rate	3.80%	3.70%
Denominated Euro with Fixed Rate
Debt Instrument [Line Items]
Unsecured debt	$ 1,715	$ 1,789
Denominated Euro with Fixed Rate | Unsecured fixed-rate debt
Debt Instrument [Line Items]
Average Rate	4.00%	4.00%
Denominated Sterling with Fixed Rate
Debt Instrument [Line Items]
Unsecured debt	$ 3,336	$ 3,412
Denominated Sterling with Fixed Rate | Unsecured fixed-rate debt
Debt Instrument [Line Items]
Average Rate	5.40%	5.40%
Denominated Yen with Fixed Rate
Debt Instrument [Line Items]
Unsecured debt	$ 389	$ 677
Denominated Yen with Fixed Rate | Unsecured fixed-rate debt
Debt Instrument [Line Items]
Average Rate	0.50%	0.40%