Conversion of preferred stock to common stock ratio.

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Operating lease payments paid for additional space.

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Operating lease termination month and year.

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Percentage of royalty rate of gross revenues .

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Area of a real estate property.

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Term of lessee's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Present value of lessee's discounted obligation for lease payments from operating lease.

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Amount of lessee's right to use underlying asset under operating lease.

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The cash inflow from the additional capital contribution to the entity.

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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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Amount of expense related to royalty payments under a contractual arrangement such as payment for mineral and drilling rights and use of technology or intellectual property.

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Date the subsidiary or equity investee issued or sold stock, in CCYY-MM-DD format.

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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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Per share or per unit amount of equity securities issued.

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Number of shares issued during the period as a result of the conversion of convertible securities.

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Number of new stock issued during the period.

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Related Party Transactions - Additional Information (Details)				1 Months Ended
	Feb. 10, 2020 USD ($) $ / shares shares	May 13, 2019 $ / shares shares	Jul. 16, 2018 ft² shares	May 31, 2020 USD ($)	Feb. 29, 2020 USD ($) $ / shares shares	May 31, 2019 USD ($) shares	Jun. 30, 2014 USD ($)	Sep. 30, 2020 USD ($)	Dec. 31, 2019 USD ($)	Jun. 30, 2018
Related Party Transaction [Line Items]
Percentage of royalties payment to stockholders in amount of gross revenues							3.00%
Lease agreement period			3 years
Restricted stock shares issued \| shares			114,437
Operating lease payments paid for additional space \| $						$ 63,000
Operating lease termination month and year				2021-07		2021-07
Operating lease asset \| $				$ 172,000				$ 848,000	$ 625,000
Operating lease liability \| $				$ 172,000		$ 0		$ 523,000
IPO
Related Party Transaction [Line Items]
Number of shares issued and sold \| shares		5,073,800
Offering price per share \| $ / shares		$ 17
Private Placement
Related Party Transaction [Line Items]
Agreement date					Feb. 10, 2020
Number of shares issued and sold \| shares					2,500,000
Proceeds from issuance of common stock \| $					$ 125,000,000
Offering price per share \| $ / shares					$ 50.00
Private Placement \| David A. Lamond
Related Party Transaction [Line Items]
Agreement date	Feb. 10, 2020
Number of shares issued and sold \| shares	30,000
Proceeds from issuance of common stock \| $	$ 1,500,000
Offering price per share \| $ / shares	$ 50.00
South San Francisco, California
Related Party Transaction [Line Items]
Area of lease office space \| ft²			3,185
Series B Redeemable Convertible Preferred Stock
Related Party Transaction [Line Items]
Lease agreement period										3 years
Series B Redeemable Convertible Preferred Stock \| IPO
Related Party Transaction [Line Items]
Conversion of preferred stock into common stock \| shares						82,649
Conversion of redeemable convertible preferred stock to common stock ratio		100.00%				100.00%
Series B Redeemable Convertible Preferred Stock \| IPO \| Series B Redeemable Convertible Preferred Stock Investor
Related Party Transaction [Line Items]
Conversion of preferred stock into common stock \| shares						229,453
Maximum
Related Party Transaction [Line Items]
Payment of royalties to stockholders \| $							$ 1,050,000