Share-Based Compensation - Narrative (Details)	12 Months Ended
Jan. 31, 2015
Omnibus Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Performance measurement period	3 years
Shares available for grant	7,000,000
Executive Plans
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance measurement period	3 years
Shares available for grant	8,568,841
Plan period	10 years
Annual maximum percent of issued common shares issuable under share plan	10.00%
Maximum percentage of shares to be granted over ten year period	10.00%
Maximum percentage of shares to be granted over ten year period including discretionary option plans	5.00%
Discount from market price	15.00%

Maximum percentage of shares to be granted over ten year period including discretionary option plans.

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- Definition

Maximum percentage of share to be grant over ten year period

+ References

No definition available.

+ Details

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- Definition

Period in which performance criteria measured

+ References

No definition available.

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- Definition

Share-based Compensation Plan, Annual Maximum Percent of Issued Common Shares Issuable under Share Plan

+ References

No definition available.

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- Definition

Share-based compensation plan period.

+ References

No definition available.

+ Details

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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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)(1)

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

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- Definition

Discount rate from fair value on purchase date that participants pay for shares.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

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

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- Definition

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)(3)

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

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