Number of shares available for sale under employee stock purchase plan.

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- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
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- Definition

Description of service or performance condition required to be met for earning right to award under share-based payment arrangement. Includes, but is not limited to, combination of market, performance or service condition.

+ References

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

Number of additional shares authorized for issuance under share-based payment arrangement.

+ References

No definition available.

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- Definition

Number of shares authorized for issuance under share-based payment arrangement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Topic 718
-SubTopic 10
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-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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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
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-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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- Definition

Maximum number of shares that may be issued in accordance with the plan as a proportion of outstanding capital stock.

+ References

No definition available.

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- Definition

Weighted average price at which option holders acquired shares when converting their stock options into shares.

+ References

No definition available.

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- Definition

Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

+ References

No definition available.

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Stock-Based Compensation - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands				1 Months Ended	3 Months Ended			9 Months Ended		12 Months Ended
	Sep. 17, 2020	Jan. 01, 2020	Jan. 01, 2019	May 07, 2021	Sep. 30, 2020	Jun. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2018
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares reserved for issuance					195,898			195,898
Options exercised, Weighted-Average Exercise Price								$ 16.11
Total stock-based compensation expense					$ 2,966		$ 391	$ 3,616	$ 865
Merger
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total stock-based compensation expense					100
Option granted	16,931
Options granted, Weighted-Average Exercise Price	$ 16.11
Merger \| Share-based Payment Arrangement, Tranche One
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting rights								one-third of the shares vesting on the first anniversary
Merger \| Share-based Payment Arrangement, Tranche Two
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting rights								one-third of the shares vesting in 12 equal monthly installments following such first anniversary
Merger \| Share-based Payment Arrangement, Tranche Three
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting rights								one-third of the shares vesting in accordance with the terms of his Transition Agreement.
CEO Stock Option Modification
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total stock-based compensation expense					$ 600
CEO Stock Option Modification \| Scenario Forecast
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total stock-based compensation expense				$ 100
2018 Stock Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of additional shares added on outstanding shares								4.00%
2017 and 2018 Stock Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares of common stock available for grant					1,462,006			1,462,006
Number of shares reserved for issuance					1,326,508			1,326,508
Options exercised, Weighted-Average Exercise Price								$ 15.64
2014 Stock Incentive Plan Member
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares reserved for issuance					69,014			69,014
Options exercised, Weighted-Average Exercise Price								$ 1.27
2015 Stock Incentive Plan Member
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares reserved for issuance					1,677,979			1,677,979
Options exercised, Weighted-Average Exercise Price								$ 6.14
2017 and 2018 Stock Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares of common stock available for grant					636,168			636,168
2018 Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of additional shares added on outstanding shares										1.00%
Number of shares reserved for issuance										39,290
Number of additional shares reserved for issuance		131,432	79,369
Number Of Shares Available For Sale Under Employee Stock Purchase Plan						0
2018 Employee Stock Purchase Plan \| Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of additional shares reserved for issuance								77,703