Short-term Borrowings and Long-term Debt - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Jan. 31, 2025	Jan. 31, 2024	Jan. 31, 2023
Debt Instrument [Line Items]
Short-term borrowings	$ 3,068	$ 878
Average interest rate	5.30%	7.70%
Letters of credit, drawn	$ 1,500	$ 1,700
Proceeds from issuance of long-term debt	0	4,967	$ 5,041
Senior Unsecured Notes
Debt Instrument [Line Items]
Proceeds from issuance of long-term debt	$ 0	4,967
Fronted and Syndicated Lines of Credit | Minimum
Debt Instrument [Line Items]
Variable rate commitment	0.0055
Commitment fee	0.00015
Fronted and Syndicated Lines of Credit | Maximum
Debt Instrument [Line Items]
Commitment fee	0.00040
Letter of Credit
Debt Instrument [Line Items]
Principal Amount	$ 2,100	$ 2,100