Cash Dividends (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	9 Months Ended
Sep. 30, 2014	Sep. 30, 2013
Dividends [Line Items]
Cash dividend declared	$ 0.15	$ 0.17
Cash dividends paid	$ 4,254	$ 4,805
Third Quarter Dividend
Dividends [Line Items]
Cash dividend declaration Date	Sep. 19, 2014	Sep. 09, 2013
Cash dividend distributed date	Oct. 22, 2014	Oct. 18, 2013
Cash dividend record date	Oct. 08, 2014	Oct. 04, 2013
Cash dividend declared	$ 0.05	$ 0.05
Cash dividends paid	1,417	1,415
Second Quarter Dividend
Dividends [Line Items]
Cash dividend declaration Date	Jun. 09, 2014	Jun. 10, 2013
Cash dividend distributed date	Jul. 17, 2014	Jul. 19, 2013
Cash dividend record date	Jul. 03, 2014	Jul. 05, 2013
Cash dividend declared	$ 0.05	$ 0.05
Cash dividends paid	1,420	1,414
First Quarter Dividend
Dividends [Line Items]
Cash dividend declaration Date	Mar. 10, 2014	Mar. 11, 2013
Cash dividend distributed date	Apr. 18, 2014	Apr. 19, 2013
Cash dividend record date	Apr. 04, 2014	Apr. 05, 2013
Cash dividend declared	$ 0.05	$ 0.07
Cash dividends paid	$ 1,417	$ 1,976

Cash dividend paid.

No definition available.

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- Details

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- Definition

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

+ References

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

+ Details

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- Definition

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

+ References

+ Details

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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.

+ Details

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