Employee Stock and Savings Plans Total Intrinsic Value of Options Exercised and Cash Received from Options Exercised (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Jan. 31, 2013	Jan. 31, 2012	Jan. 31, 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Intrinsic value of options exercised	$ 21,647	$ 15,802	$ 7,812
Proceeds from Stock Options Exercised	$ 24,262	$ 15,194	$ 8,639

The cash inflow associated with the amount received from holders exercising their stock options. This item inherently excludes any excess tax benefit, which the entity may have realized and reported separately.

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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+ Details