Reduction to research and development expense.

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Summary of significant accounting policies.

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Amount, before allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current.

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-Publisher FASB
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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable.

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Amount after tax of increase (decrease) to equity or (increase) decrease to net assets, resulting from the cumulative effect adjustment of a new accounting principle applied in the period of adoption.

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Indicates (true false) whether practical expedients are elected for not reassessing whether any expired or existing contract is or contains lease, lease classification for expired or existing lease, and initial direct cost for any existing lease.

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Represents the quantification of the effect of adopting the new accounting standard or change in accounting principle expected by the entity to have a significant effect on the entity's financial statements.

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Jan. 01, 2018	Dec. 31, 2017
Summary Of Significant Accounting Policies [Line Items]
Cumulative adjustment to accumulated deficit				$ 207
Deferred revenue from a license and collaboration agreement	$ 15,000
Reduction to research and development expenses	0	$ 50
Accounts receivable	$ 15,000
Software
Summary Of Significant Accounting Policies [Line Items]
Estimated useful lives	3 years
Computer equipment
Summary Of Significant Accounting Policies [Line Items]
Estimated useful lives	3 years
Furniture \| Minimum
Summary Of Significant Accounting Policies [Line Items]
Estimated useful lives	3 years
Furniture \| Maximum
Summary Of Significant Accounting Policies [Line Items]
Estimated useful lives	7 years
Leasehold improvements \| Minimum
Summary Of Significant Accounting Policies [Line Items]
Estimated useful lives	3 years
Leasehold improvements \| Maximum
Summary Of Significant Accounting Policies [Line Items]
Estimated useful lives	7 years
Accumulated Deficit
Summary Of Significant Accounting Policies [Line Items]
Cumulative adjustment to accumulated deficit				$ 207
AS 2016-02
Summary Of Significant Accounting Policies [Line Items]
Lease practical expedients	true
Impact of new lease accounting standard on assets and liabilities	$ 2,100
ASU 2014-09 \| ISU Abxis \| Difference between Revenue Guidance in Effect before and after Topic 606 \| Accumulated Deficit
Summary Of Significant Accounting Policies [Line Items]
Cumulative adjustment to accumulated deficit			$ 200