STOCKHOLDERS' EQUITY - Information Regarding All Stock Options (Detail 1) (USD $)	12 Months Ended
Jan. 31, 2015	Jan. 31, 2014	Jan. 31, 2013
Shares
Stock options outstanding at beginning of year	268,488	382,054	417,722
Exercised	(33,900)	(109,766)	(120,518)
Granted			85,000
Cancelled or forfeited		(3,800)	(150)
Stock options outstanding at end of year	234,588	268,488	382,054
Exercisable	125,088	159,238	224,121
Weighted Average Exercise Price
Stock options outstanding at beginning of year	$ 22.21	$ 20.79	$ 16.59
Exercised	$ 21.51	$ 17.36	$ 11.82
Granted			$ 28.72
Cancelled or forfeited		$ 19.39	$ 18.40
Stock options outstanding at end of year	$ 22.32	$ 22.21	$ 20.79
Exercisable	$ 17.26	$ 18.65	$ 16.89

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.

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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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.

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For presentations that combine terminations, the number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan or that expired.

+ References

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

-Publisher FASB

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-Subparagraph (c)(1)(iv)(3)-(4)

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Weighted average price of options that were either forfeited or expired.

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

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

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

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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

+ References

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

-Publisher SEC

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