Short-term Borrowings and Long-term Debt - Schedule of Significant Debt Repayments (Details) ¥ in Millions, $ in Millions	12 Months Ended
	Jan. 31, 2026 USD ($)	Jan. 31, 2025 USD ($)	Jan. 31, 2025 JPY (¥)
Debt Instrument [Line Items]
Significant repayments of long-term debt	$ 2,625	$ 3,373
3.550% Debt, Due June 2025 \| Unsecured debt
Debt Instrument [Line Items]
Principal Amount	$ 875
Interest Rate	3.55%
Significant repayments of long-term debt	$ 875
3.900% Debt, Due September 2025 \| Unsecured debt
Debt Instrument [Line Items]
Principal Amount	$ 1,750
Interest Rate	3.90%
Significant repayments of long-term debt	$ 1,750
3.30% Debt, Due April 2024 \| Unsecured debt
Debt Instrument [Line Items]
Principal Amount		$ 1,500
Interest Rate		3.30%	3.30%
Significant repayments of long-term debt		$ 1,500
2.85% Debt, Due July 2024 \| Unsecured debt
Debt Instrument [Line Items]
Principal Amount		$ 990
Interest Rate		2.85%	2.85%
Significant repayments of long-term debt		$ 990
0.298% Debt, Due July 2024 \| Unsecured debt
Debt Instrument [Line Items]
Principal Amount \| ¥			¥ 40,000
Interest Rate		0.298%	0.298%
Significant repayments of long-term debt		$ 253
2.650% Debt, Due December 2024 \| Unsecured debt
Debt Instrument [Line Items]
Principal Amount		$ 630
Interest Rate		2.65%	2.65%
Significant repayments of long-term debt		$ 630