Common stock initially reserved for issuance.

No definition available.

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- Definition

Equity distribution agreement aggregate offering price.

+ References

No definition available.

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- Definition

Shares available for issuance under plan annual increase rate.

+ References

No definition available.

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- Definition

Face amount or stated value per share of common stock.

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- Definition

The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

+ References

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- Definition

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

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

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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

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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- Definition

The number of shares or units of entity securities issued in the transaction in which equity securities were issued to pay for goods or nonemployee services.

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- Definition

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

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- Definition

Number of new stock issued during the period.

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Stockholders' Equity - Employee Stock Purchase Plan - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended	12 Months Ended
	Oct. 31, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Feb. 29, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for issuance under Plan		2,192,545	1,708,516
Aggregate limit of common stock		200,000,000	200,000,000
Company's incremental common stock shares reserved for issuance		2,000,000
Stock options grant shares approved for issuance-Non Employee		82,011	28,534	239,266
Common stock, par value		$ 0.001	$ 0.001
Stock issued during period, shares, new issues		6,491,196
Proceeds from issuance of common stock		$ 73,276	$ 0	$ 0
Equity Distribution Agreement [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity distribution agreement offering price			$ 75,000
ESPP [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for issuance under Plan		622,898
Common stock initially reserved for issuance					300,000
Shares available for issuance under plan annual increase rate					1.00%
Company's incremental common stock shares reserved for issuance	300,000
Common stock issued to employees		71,653	88,784	93,221
Unrecognized compensation expenses		$ 200
Unrecognized compensation expense, weighted-average period		4 months 24 days
ESPP [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for issuance under Plan		1,400,000
Aggregate limit of common stock					3,000,000