Earnings per share (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
May 01, 2015	May 02, 2014
Net Income
Basic Earnings	$ 253,235	$ 222,398
Diluted Earnings	$ 253,235	$ 222,398
Shares
Shares outstanding, basic	301,202,000	309,331,000
Effect of dilutive share-based awards	887,000	964,000
Shares outstanding, diluted	302,089,000	310,295,000
Per Share Amount
Basic earnings per share (in dollars per share)	$ 0.84us-gaap_EarningsPerShareBasic	$ 0.72us-gaap_EarningsPerShareBasic
Diluted earnings per share (in dollars per share)	$ 0.84us-gaap_EarningsPerShareDiluted	$ 0.72us-gaap_EarningsPerShareDiluted
Share-based awards outstanding excluded from computation of diluted earnings per share	1,100,000	1,500,000

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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