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Long-Term Debt and Other Financings - Servier Loan Agreement - Additional Information (Details) |  | 1 Months Ended | 12 Months Ended |
--- | --- | --- | --- | ---
Aug. 25, 2017 USD ($) € / $ | Dec. 31, 2010 USD ($) | Dec. 31, 2017 USD ($) | Dec. 31, 2010 EUR (€)
Debt Instrument [Line Items] |  |  |  |
Loss on extinguishment of debt |  |  | $ 650,000 |
Servier Loan [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Date of agreement |  | Dec. 31, 2010 |  |
Borrowing capacity under loan agreement |  | $ 19,500,000 |  | € 15,000,000
Payment of debt through cash by NIBR | $ 14,300,000 |  |  |
Euro to US Dollar exchange rates | € / $ | 1.1932 |  |  |
Loss on extinguishment of debt |  |  | $ 100,000 |

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