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Treasury Stock - Additional Information (Detail) (USD $) In Millions, except Share data, unless otherwise specified | 1 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Oct. 31, 2013 | Oct. 31, 2012 | Oct. 31, 2011 | Jun. 30, 2014 | Dec. 31, 2013
Equity [Abstract] |  |  |  |  |
Share repurchase new limit amount | $ 25.0 | $ 25.0 | $ 25.0 |  |
Share repurchase program expiration date |  |  |  | Dec. 31, 2014 |
Shares repurchased |  |  |  | 1,258,250 | 1,258,250
Shares repurchased, value |  |  |  | $ 22.4 |
Shares repurchased, average price |  |  |  | $ 17.78 |

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- Definition Share Purchased Under Share Repurchase Program Value + References No definition available. + Details
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- Definition Share Repurchase Agreement Expiration Date + References No definition available. + Details
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- Definition Share Repurchases Price Paid Per Share + References No definition available. + Details
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- Details
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- Definition Amount of a stock repurchase plan authorized by an entity's Board of Directors. + References No definition available. + Details
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- Definition Number of common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.28,29) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 29, 30 -Article 5 + Details
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