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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.

+ Details

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- Definition

Total cost of shares repurchased divided by the total number of shares repurchased.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 30

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6405813&loc=d3e23239-112655

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- Definition

Cost basis for treasury stock acquired for purposes other than retirement.

+ References

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Name:	us-gaap_TreasuryStockCarryingBasis
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- Definition

Number of common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.28,29)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: 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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Treasury Stock - Additional Information (Detail) (USD $)	3 Months Ended
	Mar. 31, 2015	Dec. 31, 2014	Oct. 31, 2014	Oct. 31, 2013	Oct. 31, 2012	Oct. 31, 2011
Equity [Abstract]
Share repurchase new limit amount			$ 25,000,000	$ 25,000,000	$ 25,000,000	$ 25,000,000
Share repurchase program expiration date	Dec. 31, 2015
Shares repurchased	1,258,250us-gaap_TreasuryStockShares	1,258,250us-gaap_TreasuryStockShares
Shares repurchased, value	$ 22,400,000us-gaap_TreasuryStockCarryingBasis
Shares repurchased, average price	$ 17.78