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           Investments and Fair Value Measurements - Additional Information (Detail) (USD $) 
        In Thousands, unless otherwise specified  | 
        
           Jun. 30, 2014 
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           Dec. 31, 2013 
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| Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items] | ||
| Investments | $ 100 | $ 103 | 
| Maximum financial interest in affiliated investment funds | 2.00% | 
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- Definition 
          The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Details 
          
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- Definition 
          Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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