Deferred Compensation (Details) - USD ($)	12 Months Ended
	Jan. 31, 2024	Jan. 31, 2023	Jan. 31, 2022
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Costs to obtain a contract	$ 210,000,000	$ 133,000,000
Amortization of costs to obtain a contract	140,000,000	138,000,000	$ 118,000,000
Impairment loss	0	0	$ 0
Rabbi Trust
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Deferred compensation liability	100,000,000	86,000,000
Deferred compensation liability, current	10,000,000	7,000,000
Deferred compensation liability, non-current	$ 90,000,000	$ 79,000,000