Stock Option Plans (Details) - Schedule of Share-based Compensation, Stock Options, Activity (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
Apr. 30, 2014	Jan. 31, 2014
Schedule of Share-based Compensation, Stock Options, Activity [Abstract]
Outstanding at January 31, 2014		83,330
Outstanding at January 31, 2014		$ 12.37
Exercised	(75,120)
Exercised	$ 12.39
Outstanding and exercisable at April 30, 2014	8,210
Outstanding and exercisable at April 30, 2014	$ 12.18
Outstanding and exercisable at April 30, 2014	36 days
Outstanding and exercisable at April 30, 2014	$ 437

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

+ References

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- Definition

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

+ 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 (c)(1)(iii)

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

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- Definition

The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

+ References

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- Definition

Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Number of options outstanding, including both vested and non-vested options.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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-Name Accounting Standards Codification

-Topic 718

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- Definition

Weighted average price at which option holders acquired shares when converting their stock options into shares.

+ References

No definition available.

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- Definition

Number of share options (or share units) exercised during the current period.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

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