Share-based Compensation Arrangement by Share-based Payment Award, Base Amount Of Common Stock Shares Authorized

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Base Number Of Options Issuable

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Increase In Number Of Shares Available For Grant, Percentage Of Shares Outstanding

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- Definition

Share-based Compensation Arrangement By Share-based Payment Award, Maximum Shares Issuable

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Vesting On A Monthly Basis

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- Definition

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

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Aggregate number of common shares reserved for future issuance.

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- Definition

Aggregate carrying value as of the balance sheet date of the liabilities for stock option plans and other equity-based compensation arrangements payable within one year (or the operating cycle, if longer).

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Aggregate carrying value as of the balance sheet date of the liabilities for stock option plans and other equity-based compensation arrangements payable after one year (or the operating cycle, if longer).

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Aggregate carrying value as of the balance sheet date of the liabilities for stock option plans and other equity-based compensation arrangements.

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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.

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

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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.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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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.

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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.

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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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.

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Number of shares issued under share-based payment arrangement.

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Percentage of vesting of award under share-based payment arrangement.

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- Definition

Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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Purchase price of common stock expressed as a percentage of its fair value.

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No definition available.

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Number of shares issued during the period as a result of an employee stock purchase plan.

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Stock-Based Compensation (Details) - USD ($) $ / shares in Units, $ in Thousands		1 Months Ended		3 Months Ended			6 Months Ended	9 Months Ended		12 Months Ended
	Jan. 30, 2020	Jul. 31, 2018	Aug. 31, 2016	Sep. 30, 2020	Jun. 30, 2020	Sep. 30, 2019	Jun. 30, 2020	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved (in shares)				6,379,826				6,379,826		28,452,008
Intrinsic value of options exercised during the period								$ 2,600
Grant date fair value of options vested during the period								$ 1,600
Grant date fair value of options vested during the period (in USD per share)								$ 18.35
Early exercise liability, current				$ 198				$ 198		$ 225
Stock-based compensation expense				2,261		$ 139		$ 5,300	$ 369
Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued pursuant to the employee stock purchase plan (in shares)					19,862		19,862
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Recognition period for unrecognized compensation costs related to unvested options expected to vest								3 years 4 months 24 days
Unrecognized compensation cost				$ 23,800				$ 23,800
Expected dividend yield								0.00%		0.00%
RSU's subject to future vesting
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved (in shares)				163,560				163,560		0
Vesting period of stock-based awards granted								4 years
Granted (in shares)								163,560		0
Recognition period for unrecognized compensation costs related to unvested options expected to vest								3 years 9 months 18 days
Unrecognized compensation cost				$ 3,900				$ 3,900
Restricted common stock vested (in shares)								0
Restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of restricted stock issued to founders (in shares)			1,187,738
Restricted stock \| First anniversary date
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting rights, percentage			25.00%
Service Condition Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of restricted stock issued to founders (in shares)			1,102,903
Service Condition Restricted Stock \| First anniversary date
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of restricted stock issued to founders (in shares)			1,102,903
Service Condition Restricted Stock \| Monthly basis
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares vesting on a monthly basis (in shares)			827,177
Performance Condition Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of restricted stock issued to founders (in shares)			84,835
Restricted common stock vested (in shares)		84,835						137,863		1,049,875
Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Increase in shares available for grant, percentage of shares outstanding	1.00%
Purchase price of common stock, as a percentage of closing trading price per share	85.00%
Stock-based compensation expense				$ 88				$ 249
Employee Stock Purchase Plan \| Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized for sale under the ESPP (in shares)	351,000
Maximum shares to be issued	5,265,000
2020 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved (in shares)	2,134,000
Increase in shares available for grant, percentage of shares outstanding	4.00%
Based number of options issuable (in shares)	11,000,000
Shares available for grant				2,280,765				2,280,765
Expected dividend yield								0.00%
2020 Equity Incentive Plan \| Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of stock-based awards granted								4 years
2017 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved (in shares)	1,550,150
Early exercise liability				$ 311				$ 311		$ 409
Early exercise liability, current				198				198		225
Early exercise liability, noncurrent				$ 113				$ 113		$ 184