Earnings per share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended	6 Months Ended
Jul. 31, 2020	Aug. 02, 2019	Jul. 31, 2020	Aug. 02, 2019
Net Income
Basic Earnings	$ 787,601	$ 426,555	$ 1,438,047	$ 811,568
Diluted Earnings	$ 787,601	$ 426,555	$ 1,438,047	$ 811,568
Shares
Shares outstanding, basic	250,281	257,793	251,031	258,407
Effect of dilutive share-based awards	1,909	1,309	1,877	1,276
Shares outstanding, diluted	252,190	259,102	252,908	259,683
Per Share Amount
Basic earnings per share (in dollars per share)	$ 3.15	$ 1.65	$ 5.73	$ 3.14
Diluted earnings per share (in dollars per share)	$ 3.12	$ 1.65	$ 5.69	$ 3.13
Share-based awards outstanding excluded from computation of diluted earnings per share	0	600	300	600

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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