Fair Values of Financial Instruments - Schedule of Fair Value of Assets and Liabilities (Details) - USD ($)	Dec. 31, 2018	Dec. 31, 2017
Investment securities, available for sale	$ 14,257,998	$ 12,724,020
Earn-out milestone liability	8,907,664	12,538,525
Corporate Debt Securities [Member]
Investment securities, available for sale	14,257,998	12,724,020
Fair Value, Measurements, Recurring [Member]
Earn-out milestone liability	8,907,664	12,538,525
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member]
Earn-out milestone liability
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Earn-out milestone liability
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member]
Earn-out milestone liability	8,907,664	12,538,525
Fair Value, Measurements, Recurring [Member] \| Corporate Debt Securities [Member]
Investment securities, available for sale	14,257,998	12,724,020
Fair Value, Measurements, Recurring [Member] \| Corporate Debt Securities [Member] \| Fair Value, Inputs, Level 1 [Member]
Investment securities, available for sale
Fair Value, Measurements, Recurring [Member] \| Corporate Debt Securities [Member] \| Fair Value, Inputs, Level 2 [Member]
Investment securities, available for sale	14,257,998	12,724,020
Fair Value, Measurements, Recurring [Member] \| Corporate Debt Securities [Member] \| Fair Value, Inputs, Level 3 [Member]
Investment securities, available for sale
Fair Value, Measurements, Non-Recurring [Member] \| In Process R&D [Member]
Liabilities, fair value	15,736,491
Fair Value, Measurements, Non-Recurring [Member] \| In Process R&D [Member]
Liabilities, fair value		20,246,491
Fair Value, Measurements, Non-Recurring [Member] \| Fair Value, Inputs, Level 1 [Member] \| In Process R&D [Member]
Liabilities, fair value
Fair Value, Measurements, Non-Recurring [Member] \| Fair Value, Inputs, Level 1 [Member] \| In Process R&D [Member]
Liabilities, fair value
Fair Value, Measurements, Non-Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| In Process R&D [Member]
Liabilities, fair value
Fair Value, Measurements, Non-Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| In Process R&D [Member]
Liabilities, fair value
Fair Value, Measurements, Non-Recurring [Member] \| Fair Value, Inputs, Level 3 [Member] \| In Process R&D [Member]
Liabilities, fair value	$ 15,736,491
Fair Value, Measurements, Non-Recurring [Member] \| Fair Value, Inputs, Level 3 [Member] \| In Process R&D [Member]
Liabilities, fair value		$ 20,246,491

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), classified as current.

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 45
-Paragraph 2
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- Definition

Amount of liability recognized arising from contingent consideration in a business combination, expected to be settled beyond one year or the normal operating cycle, if longer.

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-Name Accounting Standards Codification
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Fair value of financial and nonfinancial obligations.

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