Debt instrument, expiration of initial interest only period.

No definition available.

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- Definition

Debt instrument interest only payment period.

+ References

No definition available.

+ Details

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- Definition

Debt Instrument number of facilities.

+ References

No definition available.

+ Details

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- Definition

Debt instrument repayment number of quarterly payment.

+ References

No definition available.

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- Definition

Non contingent and non refundable minimum gross proceeds from equity financing and strategic partnerships.

+ References

No definition available.

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Balance Type:	debit
Period Type:	duration

- Definition

Aggregate number of common shares reserved for future issuance.

+ References

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Balance Type:	na
Period Type:	instant

- Definition

The price per share of the conversion feature embedded in the debt instrument.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
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- Definition

Description of conversion terms for debt instrument.

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- Definition

Threshold period of specified consecutive trading days within which common stock price to conversion price of convertible debt instrument must exceed threshold percentage for specified number of trading days to trigger conversion feature.

+ References

No definition available.

+ Details

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- Definition

Threshold number of specified trading days that common stock price to conversion price of convertible debt instruments must exceed threshold percentage within a specified consecutive trading period to trigger conversion feature.

+ References

No definition available.

+ Details

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- Definition

Description of the frequency of periodic payments (monthly, quarterly, annual).

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
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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.

+ References

No definition available.

+ Details

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- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

+ References

No definition available.

+ Details

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- Definition

Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

+ References

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Balance Type:	credit
Period Type:	instant

- Definition

Date the credit facility terminates, in YYYY-MM-DD format.

+ References

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

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- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

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- Definition

Including the current and noncurrent portions, aggregate carrying value as of the balance sheet date of loans payable (with maturities initially due after one year or beyond the operating cycle if longer).

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- Definition

The cash inflow from a debt initially having maturity due after one year or beyond the operating cycle, if longer.

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- Definition

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Convertible Debt Agreement- Additional Information (Details)		3 Months Ended		12 Months Ended
	Sep. 29, 2020 USD ($) Facility TradingDay Installment $ / shares	Mar. 31, 2022 USD ($)	Dec. 31, 2020 USD ($) shares	Dec. 31, 2021 USD ($) shares	Dec. 31, 2020 USD ($) shares
Debt Instrument [Line Items]
Loan agreement, advanced amount					$ 10,000,000
Shares of common stock reserved for future issuances \| shares			8,144,710	21,805,776	8,144,710
Common Stock Issuable Upon Conversion of Outstanding Debt
Debt Instrument [Line Items]
Shares of common stock reserved for future issuances \| shares			2,439,024	2,439,024	2,439,024
Loan and Security Agreement
Debt Instrument [Line Items]
Debt instrument, terms of conversion description				The Company has the right to convert at any time any portion of the then outstanding borrowings and all accrued but unpaid interest into shares of the Company’s common stock, at the applicable conversion price, subject to the fulfillment of both of the following conditions: (i) during a period of 30 consecutive trading days prior to the date on which the Company provides notice of the exercise of its conversion right, the closing price of the Company’s common stock was higher than 1.4 times the applicable conversion price of the term loans on at least 20 trading days, including on the trading day preceding the date on which the Company provides notice of the exercise of its conversion right, (ii) the number of shares of common stock issuable upon conversion by the Company shall not exceed the average weekly number of shares of the Company’s common stock traded on the stock market for the four weeks immediately preceding the date on which the Company provides notice of the exercise of its conversion right.
Debt instrument conversion threshold consecutive trading days \| TradingDay	30
Loan and Security Agreement \| Minimum
Debt Instrument [Line Items]
Debt instrument conversion threshold trading days \| TradingDay	20
Loan and Security Agreement \| Pontifax
Debt Instrument [Line Items]
Loan agreement, maximum borrowing capacity	$ 25,000,000.0
Number of term loan facilities \| Facility	3
Fixed interest rate on loan amounts outstanding	9.00%
Loan and security agreement, term	48 months
Loan and security agreement, interest only payment period	24 months
Expiration of interest only period	Sep. 29, 2022
Loan and security agreement, number of quarterly payments \| Installment	8
Loan and security agreement, frequency of payments				quarterly
Conversion price for borrowings outstanding \| $ / shares	$ 4.10
Debt instrument, terms of conversion description				Pontifax, at its option, has the right to convert at any time any portion of the then outstanding borrowings and all accrued but unpaid interest into shares of the Company’s common stock, at the applicable conversion price. The conversion price for borrowings outstanding under the Pontifax Agreement is fixed at $4.10 per share. If the Company consummates a stock split, stock combination, reclassification payment of stock dividend, recapitalization or other similar transaction (each a “Stock Event”), then the applicable conversion price will be proportionately increased or decreased as necessary to reflect the proportionate change in shares of the Company’s common stock issued and outstanding as a result of such Stock Event.
Outstanding principal balance				$ 10,000,000.0
Loan and Security Agreement \| Pontifax \| Subsequent Event
Debt Instrument [Line Items]
Principal prepayments		$ 5,000,000.0
Outstanding principal balance		$ 5,000,000.0
Loan and Security Agreement \| Pontifax \| Initial Loan
Debt Instrument [Line Items]
Loan agreement, advanced amount	$ 10,000,000.0
Loan and Security Agreement \| Pontifax \| Credit Line
Debt Instrument [Line Items]
Loan agreement, remaining borrowing capacity	$ 5,000,000.0
Loan and security agreement, percentage fee paid	1.00%
Unused credit facility expiration date	Sep. 29, 2021
Loan and Security Agreement \| Pontifax \| Third Installment Loan
Debt Instrument [Line Items]
Loan and security agreement, percentage fee paid	1.00%
Loan and security agreement, available borrowing capacity subject to achievement of milestones	$ 10,000,000.0		$ 10,000,000		$ 10,000,000
Non-contingent, non-refundable gross proceeds from one or more equity financings and/or strategic partnerships	$ 15,000,000.0		$ 15,000,000
Unused credit facility expiration date	Dec. 29, 2021