Dividend Announced (Detail) (Subsequent Event, Dividend Declared, USD $)	6 Months Ended
Jun. 30, 2013
Subsequent Event \| Dividend Declared
Subsequent Event [Line Items]
Quarterly dividend per share	$ 0.16
Declaration date	Jul. 30, 2013
Record date	Aug. 26, 2013
Payment date	Sep. 16, 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

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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.

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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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