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Percentage of amount employee to repay for resigns or terminated.

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Retention agreement received salary adjustment percentage.

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Run-off insurance amount.

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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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.

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Exercise price per share or per unit of warrants or rights outstanding.

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Number of warrants or rights outstanding.

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Number of shares issued for each share of convertible preferred stock that is converted.

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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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Per share conversion price of preferred stock.

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Face amount or stated value per share of preferred stock nonredeemable or redeemable solely at the option of the issuer.

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Total number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) issued to shareholders (includes related preferred shares that were issued, repurchased, and remain in the treasury). May be all or portion of the number of preferred shares authorized. Excludes preferred shares that are classified as debt.

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Proceeds from issuance of capital stock which provides for a specific dividend that is paid to the shareholders before any dividends to common stockholders and which takes precedence over common stockholders in the event of liquidation.

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

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The number of positions eliminated during the period as a percentage of total positions eliminated during the period in connection with the restructuring plan(s).

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The cumulative amount of the reporting entity's undistributed earnings or deficit.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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Period between issuance and expiration of outstanding warrant and right embodying unconditional obligation requiring redemption by transferring asset at specified or determinable date or upon event certain to occur, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Nature of Business - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands			1 Months Ended	3 Months Ended
	May 03, 2022	Jan. 28, 2022	Mar. 31, 2022	Mar. 31, 2022	May 31, 2022	May 09, 2022	May 05, 2022	Dec. 31, 2021
Class Of Stock [Line Items]
Accumulated deficit			$ (258,265)	$ (258,265)				$ (246,452)
Cash and cash equivalents			8,895	$ 8,895				$ 29,988
Directors' & Officers' run off insurance amount			$ 6,800
Restructuring charges, number of workforce headcount reduction percentage			40.00%
Preferred stock issued			0	0				0
Preferred stock par value			$ 0.001	$ 0.001				$ 0.001
Exercise price of warrants			$ 1.26	$ 1.26				$ 1.26
Loan and Security Agreement \| Pontifax
Class Of Stock [Line Items]
Voluntary principal repayments				$ 5,000
Outstanding principal balance			$ 5,000	$ 5,000				$ 10,000
Retention Plan
Class Of Stock [Line Items]
Retention agreement received salary adjustment percentage		6.50%
RSUs granted		2,998,500
Employees retention payment		$ 3,000
Percentage of amount employee to repay for resigns or terminated		50.00%
Subsequent Event \| Securities Purchase Agreement
Class Of Stock [Line Items]
Preferred stock issued	2,872.1376
Preferred stock par value	$ 1,000
Net proceeds from issuance of preferred stock	$ 2,300
Conversion price	$ 0.16
Subsequent Event \| Securities Purchase Agreement \| Series D Preferred Stock
Class Of Stock [Line Items]
Preferred stock par value	$ 0.001
Conversion of preferred stock	8,975,430						8,975,430
Conversion price	$ 0.16
Subsequent Event \| Securities Purchase Agreement \| Series E Preferred Stock
Class Of Stock [Line Items]
Preferred stock par value	$ 0.001
Conversion of preferred stock	8,975,430					8,975,430
Conversion price	$ 0.16
Subsequent Event \| HCW Warrants
Class Of Stock [Line Items]
Warrant issued	1,256,561
Exercise price of warrants	$ 0.20				$ 0.20
Warrant term	5 years
Subsequent Event \| 2022 Common Warrants
Class Of Stock [Line Items]
Warrant issued	22,438,575
Exercise price of warrants	$ 0.1694				$ 0.1694
Warrant term	5 years