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Amount of stock repurchase plan authorized.

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- Definition

Amount remaining of a stock repurchase plan authorized.

+ References

No definition available.

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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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Number of shares that have been repurchased during the period and are being held in treasury.

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- Definition

Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

+ 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

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-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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-SubTopic 30

-Section 45

-Paragraph 1

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Stockholders' Equity - Additional Information (Detail) (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Oct. 22, 2014	Nov. 01, 2007
Equity, Class of Treasury Stock [Line Items]
Stock repurchase program, additional authorized amount			$ 30,000,000
Repurchased shares	0us-gaap_TreasuryStockSharesAcquired	605,419us-gaap_TreasuryStockSharesAcquired
Repurchased shares, value		6,900,000
Stock repurchase program, average cost		$ 11.20
Stock repurchase program, remaining available repurchase amount	34,400,000
Maximum [Member]
Equity, Class of Treasury Stock [Line Items]
Stock repurchase program, additional authorized amount				$ 50,000,000