Number of equity incentive plans.

No definition available.

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- Definition

Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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- Definition

Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

+ References

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- Definition

Amount of cost to be recognized for option under share-based payment arrangement.

+ References

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- Definition

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (d)(2)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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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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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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- Definition

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

+ References

No definition available.

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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- Definition

Description of the reverse stock split arrangement. Also provide the retroactive effect given by the reverse split that occurs after the balance sheet date but before the release of financial statements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SAB Topic 4.C)
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Stock-Based Compensation - Additional Information (Details) $ / shares in Units, $ in Millions	1 Months Ended	9 Months Ended
	Feb. 28, 2019 IncentivePlan shares	Sep. 30, 2021 USD ($) $ / shares shares	Sep. 30, 2020 $ / shares	Dec. 31, 2020 shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of equity incentive plans \| IncentivePlan	2
Number of common shares, granted		1,371,000
Number of shares available for future grant		1,400,000		900,000
Weighted average grant-date fair value of options granted \| $ / shares		$ 10.53	$ 3.64
Unrecognized compensation expense \| $		$ 26.8
Weighted-average period of unrecognized compensation expense		2 years 9 months 18 days
Restricted Stock Units (RSUs)
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted-average period of unrecognized compensation expense		2 years 3 months 18 days
Total fair value of restricted stock units vested during the period \| $		$ 0.4
Unrecognized stock-based compensation expense related to RSUs \| $		$ 10.5
2009 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of common shares, granted	0
2015 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Reverse stock split	one-for-five
2015 ESPP
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares available for future grant		0.7