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Number of shares that have been repurchased and retired during the period.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29, 30

-Article 5

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- Definition

Equity impact of the value of stock that has been repurchased and retired during the period. The excess of the purchase price over par value can be charged against retained earnings (once the excess is fully allocated to additional paid in capital).

+ References

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- Definition

Amount of stock repurchase plan authorized.

+ References

No definition available.

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- Definition

Expiration date for the purchase of an entity's own shares under a stock repurchase plan, in the CCYY-MM-DD format.

+ References

No definition available.

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Stock Repurchase Program - Additional Information (Detail) (USD $)	9 Months Ended	12 Months Ended		2 Months Ended
	Jan. 31, 2015	Jan. 31, 2015	Feb. 02, 2013	Apr. 10, 2015	May 22, 2014
Equity, Class of Treasury Stock [Line Items]
Stock repurchase program, Expiration date	May 31, 2016
Repurchase and retirement of common stock, shares	269,000
Repurchase and retirement of common stock	$ 4,803,000	$ 4,803,000	$ 16,622,000
Subsequent Event [Member]
Equity, Class of Treasury Stock [Line Items]
Repurchase and retirement of common stock, shares				40,000
Repurchase and retirement of common stock				955,000
Maximum [Member]
Equity, Class of Treasury Stock [Line Items]
Stock repurchase program, Authorized amount					$ 30,000,000