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           Income Taxes - Income tax provision (Details) (USD $) 
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        12 Months Ended | ||
|---|---|---|---|
| 
           Dec. 31, 2013 
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           Dec. 31, 2012 
         | 
        
           Dec. 31, 2011 
         | 
      |
| Income Tax Disclosure [Abstract] | |||
| Current, Federal | $ 10,113,618 | $ 9,135,447 | $ (10,073,322) | 
| Current, State | 3,499,649 | 732,514 | (273,221) | 
| Current, Foreign | 370,837 | 177,713 | (277,157) | 
| Current, Total | 13,984,104 | 10,045,674 | (10,623,700) | 
| Deferred, Federal | (10,315,323) | (2,586,080) | 18,724,198 | 
| Deferred, State | (2,098,983) | 85,387 | 1,826,239 | 
| Deferred, Foreign | (1,225,117) | (1,298,228) | 840,435 | 
| Deferred, Total | (13,639,423) | (3,798,921) | 21,390,872 | 
| Income tax (benefit) provision | $ 344,681 | $ 6,246,753 | $ 10,767,172 | 
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- Definition 
          Amount of current federal tax expense (benefit) pertaining to income (loss) from continuing operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition 
          Amount of current foreign income tax expense (benefit) pertaining to income (loss) from continuing operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition 
          Amount of current income tax expense (benefit) pertaining to taxable income (loss) from continuing operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition 
          Amount of current state and local tax expense (benefit) pertaining to income (loss) from continuing operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition 
          Amount of deferred federal income tax expense (benefit) pertaining to income (loss) from continuing operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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| X | ||||||||||
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- Definition 
          Amount of deferred foreign income tax expense (benefit) pertaining to income (loss) from continuing operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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| X | ||||||||||
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- Definition 
          Amount of deferred income tax expense (benefit) pertaining to income (loss) from continuing operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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| X | ||||||||||
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- Definition 
          Amount of deferred state and local tax expense (benefit) pertaining to income (loss) from continuing operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Details 
          
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- Definition 
          Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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