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Contractual interest rate for funds borrowed, under the debt agreement.

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The cash inflow associated with the amount received by a corporation from a shareholder during the period.

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Financial Condition and Business Plan (Details Narrative) - USD ($)				1 Months Ended				9 Months Ended		12 Months Ended
	Jun. 16, 2021	Mar. 19, 2021	Aug. 28, 2020	Jun. 18, 2021	Jan. 31, 2021	Sep. 30, 2020	Jun. 30, 2018	Sep. 30, 2021	Sep. 29, 2021	Dec. 31, 2019	Dec. 31, 2018	Apr. 05, 2021	Dec. 31, 2020	Sep. 30, 2018
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Cumulative net losses								$ 328,548,285					$ 312,000,341
Cash and cash equivalents, restricted cash, short-term investments, interest receivable								60,600,000
Receivable on sale of net operating losses								$ 1,850,000
Horizon Credit Agreement [Member] \| Horizon Technology Finance Corporation [Member]
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Proceeds from Contributed Capital							$ 10,000,000
Debt Instrument, Face Amount			$ 10,000,000
Horizon Credit Agreement [Member] \| Horizon Technology Finance Corporation [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Debt Instrument, Interest Rate, Stated Percentage														7.625%
SVB Loan Facility [Member]
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Debt Instrument, Description				Payments under the loan agreement are interest only for the first 24 months after loan closing, followed by a 24-month amortization period of principal and interest through the scheduled maturity date.				Payments under the loan agreement are interest only (calculated based on one-month LIBOR plus 7.625%) for the first 24 months through July 2020, followed by a 21-month amortization period of principal and interest starting on August 1, 2020 and ending through the scheduled maturity date
Debt Instrument, Interest Rate, Stated Percentage				3.25%
Line of Credit Facility, Maximum Borrowing Capacity				$ 10,000,000
Line of Credit Facility, Remaining Borrowing Capacity				$ 4,000,000
SVB Loan Facility [Member] \| Silicon Valley Bank [Member]
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity								$ 10,000,000
Line of Credit Facility, Remaining Borrowing Capacity								$ 4,000,000
SVB Loan Facility [Member] \| Prime Rate [Member] \| Silicon Valley Bank [Member]
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Debt Instrument, Interest Rate, Stated Percentage								3.25%
SVB Loan Facility [Member] \| Horizon Technology Finance Corporation [Member]
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Repayment of outstanding in-debtedness amount								$ 6,000,000
Amendment to Horizon Credit Agreement [Member] \| Horizon Technology Finance Corporation [Member]
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Repayments of Notes Payable			5,000,000
Debt Instrument, Face Amount			5,000,000
Debt instrument related end term charges			$ 200,000
Capital on DemandTM Sales Agreement [Member] \| Jones Trading Institutional Services, LLC [Member]
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Cash and cash equivalents, restricted cash, short-term investments, interest receivable								60,600,000
Proceeds from Contributed Capital		$ 6,900,000
Debt Instrument, Face Amount					$ 35,000,000							$ 15,000,000
Proceeds from Warrant Exercises					$ 1,500,000
New Jersey [Member]
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Net proceeds from sale of net operating losses	$ 1,600,000					$ 2,000,000.0		$ 20,000,000	$ 15,000,000	$ 12,200,000	$ 13,000,000
New Jersey [Member] \| Maximum [Member]
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Net proceeds from sale of net operating losses	$ 1,400,000