Equity impact of the value of stock that has been repurchased and retired during the period. The excess of the purchase price over par value can be charged against retained earnings (once the excess is fully allocated to additional paid in capital).

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Supplemental Financial Information - Share Repurchase Program (Details) - USD ($)	3 Months Ended	9 Months Ended
	Oct. 31, 2020	Oct. 31, 2020	Nov. 02, 2019	Oct. 16, 2018	Nov. 17, 2016	Nov. 16, 2016
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Authorized repurchase amount					$ 1,000,000,000.0	$ 3,250,000,000
Stock repurchase program, additional authorized amount				$ 700,000,000
Remaining available for future share repurchases (in shares)	$ 564,500,000	$ 564,500,000
Number of common shares repurchased and retired during period (in shares)	0	1,300,000	3,000,000.0
Value of common shares repurchased and retired during period		$ 25,200,000	$ 64,300,000