Share Based Compensation (Details) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
Jan. 31, 2012 Y Plans	Jan. 31, 2011	Jan. 31, 2010
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of share based compensation plans	2
Granted, number of options	136,000
Stock options vesting period, years	4 years
Stock options expiration term, years	five years
Intrinsic value of options exercised	$ 2,362	$ 1,102	$ 314
Total compensation cost for non-vested awards not yet recognized in the Company's statements of income	4,360
Weighted average period to recognize costs associated with non-vested awards in years	2.96
2010 Stock Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock awards and incentive or non-qualified option term, years	10
Shares reserved for grant under the plan	500,000
Remaining shares available for grant	202,000
Compensation costs related to the plan	$ 64		$ 144
Granted, number of options	1,000	0	4,800
Director [Member] \| Deferred Compensation, Share-based Payments [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares reserved for grant under the plan	50,000

Number of share based compensation plans

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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- Definition

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.

+ References

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-Publisher FASB

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- Definition

The weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, using a decimal to express in number of years.

+ References

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- Definition

The date when the equity-based award expires as specified in the award agreement, which may be presented in a variety of ways (for example, year, month and year, day, month and year, quarter of a year).

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Description of the period of time over 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, which may be expressed in a variety of ways (for example, in years, month and year).

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The maximum vesting term over 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.

+ References

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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).

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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- Definition

The total accumulated difference between fair values of underlying shares on dates of exercise and exercise price on options which were exercised (or share units converted) into shares during the reporting period under the plan.

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- Definition

Net number of share options (or share units) granted during the period.

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