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STOCK-BASED COMPENSATION - Summary of Activity under Company's Stock Option Plans (Details 2) - $ / shares | 9 Months Ended | 12 Months Ended
--- | --- | ---
Oct. 31, 2015 | Oct. 31, 2014 | Jan. 31, 2015 | Jan. 31, 2014
STOCK-BASED COMPENSATION |  |  |  |
Shares, Outstanding, Beginning balance | 876,350 | 916,150 | 916,150 |
Shares, Granted | 240,000 | 220,500 |  |
Shares, Exercised | (96,450) | (243,300) |  |
Shares, Forfeited | (6,000) |  |  |
Shares, Outstanding, Ending balance | 1,013,900 | 893,350 | 876,350 | 916,150
Shares, Exercisable | 668,900 | 597,850 |  |
Weighted Average Exercise Price, Outstanding, Beginning balance | $ 22.34 | $ 17.36 | $ 17.36 |
Weighted Average Exercise Price, Granted | 35.76 | 28.84 |  |
Weighted Average Exercise Price, Exercised | 17.31 | 15.96 |  |
Weighted Average Exercise Price, Forfeited | 17.33 |  |  |
Weighted Average Exercise Price, Outstanding, Ending balance | 26.03 | 20.57 | $ 22.34 | $ 17.36
Weighted Average Exercise Price, Exercisable | $ 21.92 | $ 16.73 |  |
Weighted Average Remaining Term, Outstanding | 6 years 11 months 23 days | 6 years 6 months 7 days | 7 years 29 days | 6 years 15 days
Weighted Average Remaining Term, Exercisable | 6 years 4 months 2 days | 5 years 9 months 7 days |  |
Weighted Average Fair Value, Outstanding | $ 6.82 | $ 5.87 | $ 6.01 | $ 5.58
Weighted Average Fair Value, Exercisable | $ 5.81 | $ 5.58 |  |

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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 + Details
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