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STOCK-BASED COMPENSATION - Summary of Change in Number of Non-Vested Options to Purchase Shares of Common Stock (Details) - $ / shares | 12 Months Ended
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Jan. 31, 2016 | Jan. 31, 2015 | Jan. 31, 2014
STOCK-BASED COMPENSATION |  |  |
Shares, Nonvested, Beginning balance | 305,500 | 303,000 | 388,500
Shares, Granted | 300,000 | 305,500 | 303,000
Shares, Vested | (305,500) | (303,000) | (384,500)
Shares, Forfeited (non-vested) |  |  | (4,000)
Shares, Nonvested, Ending balance | 300,000 | 305,500 | 303,000
Weighted Average Fair Value, Nonvested, Beginning balance | $ 7.14 | $ 4.40 | $ 5.67
Weighted Average Fair Value, Granted | 8.97 | 7.14 | 4.40
Weighted Average Fair Value, Vested | 7.23 | 4.40 | 5.67
Weighted Average Fair Value, Forfeited (non-vested) |  |  | 5.71
Weighted Average Fair Value, Nonvested, Ending balance | $ 8.97 | $ 7.14 | $ 4.40

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- Definition Gross number of share options (or share units) granted during the period. + References No definition available. + Details
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- Definition The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology. + 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 (d)(1) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition Number of non-vested options outstanding. + References No definition available. + Details
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- Definition Weighted average grant-date fair value of non-vested options forfeited. + References No definition available. + Details
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