Debt - Convertible Debt (Details) - Convertible Debt [Member] - USD ($) |
12 Months Ended | |||
|---|---|---|---|---|
Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
Jun. 29, 2015 |
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| Debt Instrument [Line Items] | ||||
| Interest expense | $ 8,767,188 | $ 8,800,842 | $ 4,472,031 | |
| Discount amortization | 738,912 | 744,081 | 380,653 | |
| Deferred debt issuance amortization | 48,276 | 48,566 | 21,656 | |
| Convertible Senior Notes Due 2020 [Member] | ||||
| Debt Instrument [Line Items] | ||||
| Interest expense | $ 7,980,000 | $ 8,008,195 | $ 4,069,722 | |
| Interest Rate | 7.00% | 7.00% | 7.00% | |
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- Definition Amount of noncash expense included in interest expense to amortize debt discount and premium associated with the related debt instruments. Excludes amortization of financing costs. Alternate captions include noncash interest expense. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of amortization expense attributable to debt issuance costs. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Contractual interest rate for funds borrowed, under the debt agreement. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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- Definition Amount of the cost of borrowed funds accounted for as interest expense for debt. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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- Details
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