EMPLOYEE BENEFIT PLANS (Details Textuals) (USD $) In Millions, unless otherwise specified	12 Months Ended
Jan. 31, 2015	Jan. 31, 2014	Jan. 31, 2013
Defined Benefit Plan Disclosure [Line Items]
Non-discretionary matching contribution			100.00%
Percentage of employee's compensation matched by employer			3.00%
Employer matching percentage of employee contributions			50.00%
Percentage of additional employee's compensation matched by employer			2.00%
Defined contribution plan, matching contributions	$ 2.0	$ 1.3	$ 1.0
Maximum
Defined Benefit Plan Disclosure [Line Items]
Defined contribution plan, employee contribution percentage for which employer contributes a matching contribution			6.00%

Represents defined contribution plan additional maximum annual contributions per employee percent.

No definition available.

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Percentage Of Employer Contribution To Match Participant Contribution In Defined Contribution Plan

No definition available.

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Amount of discretionary contributions made by an employer to a defined contribution plan.

No definition available.

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Data Type:	xbrli:monetaryItemType
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Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

No definition available.

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Percentage employer matches of the employee's percentage contribution matched.

No definition available.

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Maximum percentage of employee gross pay the employee may contribute to a defined contribution plan.

No definition available.

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