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Treasury Stock - Additional Information (Detail) (USD $) In Millions, unless otherwise specified | 1 Months Ended | 3 Months Ended | 6 Months Ended
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Oct. 31, 2011 | Jun. 30, 2013 | Jun. 30, 2012 | Jun. 30, 2013 | Jun. 30, 2012
Treasury Stock Textual [Abstract] |  |  |  |  |
Share repurchase program, new limit amount | $ 25.0 |  |  |  |
Treasury stock, shares purchased |  | 0 | 0 | 0 | 0

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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 shares that have been repurchased during the period and are being held in treasury. + 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 + Details
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