Subsequent offering period.

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- Definition

Aggregate number of common shares reserved for future issuance.

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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

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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

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

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- Definition

Discount rate from fair value on purchase date that participants pay for shares.

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

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Stock-based Compensation - Additional Information (Details) - USD ($) $ in Millions		9 Months Ended
	Feb. 06, 2019	Sep. 30, 2020	Jun. 30, 2020	Jan. 01, 2020
2019 Equity Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected weighted average period		2 years 9 months 18 days
Common stock reserved for issuance	7,688,156	15,618,644		3,452,643
Common stock, shares available for issuance			5,585,374
Unrecognized stock-based compensation		$ 73.3
2019 Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock reserved for issuance		1,974,319
Purchase price of common stock, percentage	85.00%
Subsequent offering period	6 months
Restricted Common Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized stock-based compensation		$ 2.1
Expected weighted average period		1 year