As of the balance sheet date, the aggregate unrecognized cost of equity-based awards made to employees under equity-based compensation awards that have yet to vest.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (i)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph h

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Share based compensation arrangement by share based payment award contractual term

+ References

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- Definition

ShareBasedCompensationArrangementByShareBasedPaymentAwardVestingPercentageYear3 - Percentage of grant that vest in the 3rd year.

+ References

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- Definition

Sharebasedcompensationarrangementbysharebasedpaymentawardvestingpercentageyear5 - percentage of grant that vest in year 5.

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- Definition

Weighted Average Discount For Dividend Yield

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Shareholder's Equity (Restricted Stock Rights) (Narrative) (Details) (USD $) In Millions, 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]
Share based compensation arrangement by share based payment award vesting percentage year 5	50.00%
Weighted average discount for dividend yield	12.20%	11.70%	9.10%
Share based compensation arrangement by share based payment award contractual term	10 years
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation arrangement by share based payment award vesting percentage year 3	50.00%
Unrecognized compensation cost	437
Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted vesting period, years	5 years
Unrecognized compensation cost	21
Maximum [Member] \| Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted vesting period, years	5 years