Earnings per share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
Apr. 29, 2016	May. 01, 2015
Net Income
Basic Earnings	$ 295,124	$ 253,235
Diluted Earnings	$ 295,124	$ 253,235
Shares
Shares outstanding, basic	285,886	301,202
Effect of dilutive share-based awards	1,092	887
Shares outstanding, diluted	286,978	302,089
Per Share Amount
Basic earnings per share (in dollars per share)	$ 1.03	$ 0.84
Diluted earnings per share (in dollars per share)	$ 1.03	$ 0.84
Share-based awards outstanding excluded from computation of diluted earnings per share	1,600	1,100

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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Net income after adjustments for dividends on preferred stock (declared in the period) and/or cumulative preferred stock (accumulated for the period).

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Net Income or Loss Available to Common Stockholders plus adjustments resulting from the assumption that dilutive convertible securities were converted, options or warrants were exercised, or that other shares were issued upon the satisfaction of certain conditions.

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