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Subsequent Events - Additional Information (Detail) (USD $) | 9 Months Ended |  |  |  | 0 Months Ended
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Sep. 30, 2014 | Oct. 31, 2013 | Oct. 31, 2012 | Oct. 31, 2011 | Oct. 28, 2014 Subsequent Event [Member] | Oct. 28, 2014 Subsequent Event [Member] Dividend Declared [Member] | Oct. 28, 2014 Subsequent Event [Member] Extraordinary Dividend [Member]
Subsequent Event [Line Items] |  |  |  |  |  |  |
Cash dividend per share |  |  |  |  |  | $ 0.12 |
Date of payment to shareholders entitled to dividends |  |  |  |  |  | Dec. 26, 2014 | Dec. 26, 2014
Date of record of shareholders entitled to dividends |  |  |  |  |  | Dec. 12, 2014 | Dec. 12, 2014
Extraordinary cash dividends declared per common share | $ 0.50 |  |  |  |  |  | $ 1.00
Share repurchase program limit amount |  | $ 25,000,000 | $ 25,000,000 | $ 25,000,000 | $ 25,000,000 |  |
Share repurchase program expiration date | Dec. 31, 2014 |  |  |  | Dec. 31, 2015 |  |

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- Definition Special cash dividend declared per share. + References No definition available. + 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 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 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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- Definition Amount of stock repurchase plan authorized. + References No definition available. + Details
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- Definition Expiration date for the purchase of an entity's own shares under a stock repurchase plan, in the CCYY-MM-DD format. + References No definition available. + Details
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- Details
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