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           Subsequent Events (Details) (Subsequent events, USD $) 
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        0 Months Ended | 
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           Apr. 04, 2014 
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           Subsequent events 
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| Subsequent Events | |
| Cash dividend declared (in dollars per share) | $ 0.045 | 
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- Definition 
          Aggregate dividends declared during the period for each share of common stock outstanding. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Details 
          
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