Stock-Based Compensation Stock Based Compensation Details Textual (Details) shares in Thousands	9 Months Ended
Oct. 31, 2015 shares
Omnibus Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Requisite Service Period	4 years
Share Based Compensation Arrangement By Share Based Payment Award Expiry Period From Date Of Grant	10 years
Employee Stock Purchase Plans [Member]
Employee Stock Purchase Plan Maximum Number Of Shares Per Buy Date That May Be Purchased By Eligible Participants	6
Share Based Compensation Arrangement By Share Based Payment Award Discounted Price From Market Price Offering	85.00%

Employee Stock Purchase Plan Maximum Number Of Shares Per Buy Date That May Be Purchased By Eligible Participants

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- Definition

The discounted price from the offering date market price or purchase date market price that participants pay for shares purchased under the employee stock purchase plan.

+ References

No definition available.

+ Details

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- Definition

Expiration date from the original grant date for options granted under share based payment awards.

+ References

No definition available.

+ Details

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- Definition

Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, 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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