Subsequent Events - Additional Information (Detail) (Subsequent Event [Member], USD $)	1 Months Ended
Jul. 30, 2013
Subsequent Event [Member]
Subsequent Event [Line Items]
Quarterly cash dividend per share	$ 0.08
Date quarterly cash dividend declared	Jul. 30, 2013
Date of payment to shareholders entitled to dividends	Sep. 27, 2013
Date of record of shareholders entitled to dividends	Sep. 13, 2013

Date the declared dividend will be paid, in CCYY-MM-DD format.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 50

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4304-108586

+ Details

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- Definition

The per share amount of a dividend declared, but not paid, as of the financial reporting date.

+ References

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- Definition

Date the dividend to be paid was declared, in CCYY-MM-DD format.

+ References

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- Definition

Date the holder must own the stock to be entitled to the dividend, in CCYY-MM-DD format.

+ References

No definition available.

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