Loan and Security Agreement - Outstanding Debt and Unamortized Debt Discount (Details) - USD ($)	Mar. 31, 2020	Dec. 31, 2019
Debt Disclosure [Abstract]
Total Outstanding Debt	$ 20,000,000	$ 20,000,000
Add: accreted liability of final payment fee	523,378	404,364
Less: unamortized debt discount, long-term	(312,573)	(405,071)
Less: current portion of long-term debt	(4,666,667)	(2,666,667)
Loan payable, long-term	15,544,138	17,332,626
Current portion of long-term debt	4,666,667	2,666,667
Current portion of unamortized debt discount	(98,235)	(64,375)
Loan payable, current portion	$ 4,568,432	$ 2,602,292

Amount of accreted liability of final payment fee.

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Amount, after noncurrent portion of unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

No definition available.

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- References

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
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Amount of debt discount to be amortized within one year or within the normal operating cycle, if longer.

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-Publisher FASB
-Name Accounting Standards Codification
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Amount of debt discount to be amortized after one year or the normal operating cycle, if longer.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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