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.

+ Details

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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
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21475-112644

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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

Face amount or stated value per share of common stock.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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- Definition

The cash outflow for cost incurred directly with the issuance of an equity security.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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-Section 45
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- Definition

The cash inflow associated with the amount received from entity's raising of capital via private rather than public placement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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

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

+ References

No definition available.

+ Details

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- Definition

Per share or per unit amount of equity securities issued.

+ References

No definition available.

+ Details

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Capital Stock (Details) $ / shares in Units, $ in Millions			9 Months Ended
Capital Stock (Details) $ / shares in Units, $ in Millions	Aug. 11, 2021 USD ($) $ / shares shares	Dec. 09, 2016	Sep. 30, 2021 $ / shares shares	Sep. 30, 2020 shares	Dec. 31, 2020 $ / shares
Stock-based compensation disclosure
Common stock, par value (in dollars per share)			$ 0.01		$ 0.01
Pre-Funded Warrants
Stock-based compensation disclosure
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
Securities Purchase Agreement \| RA Capital Healthcare Fund, L.P. \| Pre-Funded Warrants
Stock-based compensation disclosure
Pre-Funded warrants issued to purchase shares \| shares	5,434,782
Common stock, par value (in dollars per share)	$ 0.01
Exercise price	5.51
Warrant exercise price	$ 5.52
Aggregate gross proceeds \| $	$ 29.9
Transaction costs \| $	$ 0.2
Stock options
Stock-based compensation disclosure
Stock options granted to directors (in shares) \| shares			4,380,000
Compensation Policy for Non-Employee Directors \| Stock options
Stock-based compensation disclosure
Stock options granted to directors (in shares) \| shares			308,000	300,000
Non-employee directors-initial grant \| Deferred share units
Stock-based compensation disclosure
Vesting period		3 years
Non-employee directors-first anniversary \| Deferred share units
Stock-based compensation disclosure
Vesting period		1 year