Represents the maximum amount of the investor's rights under the Pre-Funded Warrant to increase or decrease percentage.

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- Definition

Represents the percentage of common stock owned that limits the number of warrants exercised.

+ References

No definition available.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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- Definition

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.

+ References

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- Definition

Aggregate number of common shares reserved for future issuance.

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- Definition

Amount of cash inflow from exercise of option under share-based payment arrangement.

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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.

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Gross number of share options (or share units) granted during the period.

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- Definition

Number of share options (or share units) exercised during the current period.

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Capital Stock (Details) $ / shares in Units, $ in Thousands	3 Months Ended		12 Months Ended
Capital Stock (Details) $ / shares in Units, $ in Thousands	Mar. 31, 2023 USD ($) shares	Mar. 31, 2022 USD ($)	Dec. 31, 2022 shares	Dec. 31, 2021 $ / shares shares	Aug. 11, 2021	Jun. 30, 2018 shares
Stock-based compensation disclosure
Proceeds from issuance of common stock under stock plans \| $	$ 39	$ 620
ESPP
Stock-based compensation disclosure
Aggregate number of common shares reserved for future issuance						2,000,000
Pre-Funded Warrants
Stock-based compensation disclosure
Warrant exercise price \| $ / shares				$ 0.01
Threshold percentage of common stock owned that limits the number of warrants exercised					9.99
Maximum percentage upon at least 61 days prior notice from the investor to the Company					19.99
Stock options
Stock-based compensation disclosure
Stock options granted to directors (in shares)	4,757,000
Options exercised (in shares)	16,000
Securities Purchase Agreement \| RA Capital Healthcare Fund, L.P. \| Pre-Funded Warrants
Stock-based compensation disclosure
Pre-Funded warrants issued to purchase shares				21,434,782
Securities Purchase Agreement \| Redmile Group LLC \| Pre-Funded Warrants
Stock-based compensation disclosure
Pre-Funded warrants issued to purchase shares				11,363,636
Compensation Policy for Non-Employee Directors \| Stock options
Stock-based compensation disclosure
Stock options granted to directors (in shares)			321,622	352,000