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The gross cash inflow, before deducting the underwriting discount and commissions and other offering expenses payable from the issuance of common stock, preferred stock, treasury stock, stock options, and other types of equity.

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

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Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.

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Face amount or stated value per share of common stock.

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The cash inflow from the issuance of common stock, preferred stock, treasury stock, stock options, and other types of equity.

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Per share or per unit amount of equity securities issued.

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No definition available.

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Number of new stock issued during the period.

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Description of management's evaluation of the significance of conditions or events in relation to the ability to meet its obligations.

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Liquidity (Narrative) (Details)					3 Months Ended
Liquidity (Narrative) (Details)	Mar. 31, 2022 USD ($) $ / shares shares	Feb. 09, 2022 USD ($) tranche $ / shares shares	Oct. 28, 2021 USD ($) $ / shares shares	Jan. 26, 2021 $ / shares shares	Mar. 31, 2022 USD ($) $ / shares shares	Mar. 31, 2021 USD ($) tranche	Dec. 31, 2021 USD ($) $ / shares
Cash and cash equivalents \| $	$ 46,408,000				$ 46,408,000	$ 22,455,000	$ 10,288,000
Liquidity, management evaluation					The Company has prepared its consolidated financial statements on a going concern basis, which assumes that the Company will realize its assets and satisfy its liabilities in the normal course of business. However, the Company has incurred net losses since its inception and has negative operating cash flows. These circumstances raise substantial doubt about the Company’s ability to continue as a going concern. The accompanying financial statements do not include any adjustments to reflect the possible future effects on the recoverability and classification of assets or the amounts and classifications of liabilities that may result from the outcome of the uncertainty concerning the Company’s ability to continue as a going concern.
Common stock, par value (in dollars per share) \| $ / shares	$ 0.01		$ 0.01		$ 0.01		$ 0.01
Securities Purchase Agreement [Member]
Proceeds from equity offerings, gross \| $			$ 7,000,000.0			20,000,000.0
Shares Issued, Price Per Share \| $ / shares			$ 3.30	$ 3.25
Securities Purchase Agreement [Member] \| Cystic Fibrosis Foundation [Member]
Stock Issued During Period, Shares, New Issues			909,091
Securities Purchase Agreement [Member] \| Innoviva Strategic Opportunities LLC [Member]
Number of tranches \| tranche		2
Shares Issued, Price Per Share \| $ / shares		$ 5.00
Stock Issued During Period, Shares, New Issues		9,000,000	1,212,122
Class of Warrant or Right, Number of Securities Called by Warrants or Rights		4,500,000
Exercise price of warrants \| $ / shares		$ 5.00
Securities Purchase Agreement [Member] \| Common Stock Subject to Mandatory Redemption [Member]
Shares Issued, Price Per Share \| $ / shares				$ 3.25
Stock Issued During Period, Shares, New Issues				6,153,847
Securities Purchase Agreement [Member] \| Warrants and Rights Subject to Mandatory Redemption [Member]
Proceeds from equity offerings, gross \| $						$ 20,000,000.0
Number of tranches \| tranche						2
Securities Purchase Agreement [Member] \| Warrants and Rights Subject to Mandatory Redemption [Member] \| Maximum [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights				6,153,847
Securities Purchase Agreement First Tranche [Member] \| Innoviva Strategic Opportunities LLC [Member]
Stock Issued During Period, Shares, New Issues		3,614,792
Class of Warrant or Right, Number of Securities Called by Warrants or Rights		1,807,396
Proceeds from issuance of common stock and warrants \| $		$ 18,100,000
Securities Purchase Agreement Second Tranche [Member] \| Innoviva Strategic Opportunities LLC [Member]
Stock Issued During Period, Shares, New Issues	5,385,208
Class of Warrant or Right, Number of Securities Called by Warrants or Rights	2,692,604				2,692,604
Proceeds from issuance of common stock and warrants \| $	$ 26,900,000