Commitments and Contingencies - Additional Information (Detail) (USD $)	9 Months Ended
Sep. 30, 2013	Sep. 30, 2012	Aug. 10, 2010
Commitments And Contingencies Disclosure [Abstract]
Purchase of outstanding shares			250,000
Repurchased and retired under stock buyback program	97,153
Average price of common stock per share	$ 7.28
Total cost of shares purchased	$ 708,000	$ 0

Stock repurchased during period average price per share.

No definition available.

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- Details

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- Definition

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

The number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan.

+ References

No definition available.

+ Details

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