Aggregate offering price of securities.

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- Definition

Proceeds from issuance of common stock net of underwriting discounts commissions and estimated offering expenses.

+ References

No definition available.

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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- Definition

Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

+ References

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- Definition

The cash outflow for cost incurred directly with the issuance of an equity security.

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- Definition

Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Per share or per unit amount of equity securities issued.

+ References

No definition available.

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- Definition

Number of shares issued in lieu of cash for services contributed to the entity. Number of shares includes, but is not limited to, shares issued for services contributed by vendors and founders.

+ References

No definition available.

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- Definition

Number of new stock issued during the period.

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- Definition

Total number of shares issued during the period, including shares forfeited, as a result of Restricted Stock Awards.

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- Definition

Value of stock issued in lieu of cash for services contributed to the entity. Value of the stock issued includes, but is not limited to, services contributed by vendors and founders.

+ References

No definition available.

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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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Stockholders' Equity - Additional Information (Detail) - USD ($)			1 Months Ended		3 Months Ended			6 Months Ended
	Jul. 29, 2019	Mar. 20, 2019	Jul. 31, 2019	May 31, 2019	Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Apr. 04, 2019	Dec. 31, 2018
Subsidiary Sale Of Stock [Line Items]
Restricted stock units vested shares				74,166
Common stock, shares issued				74,166	40,027,916			40,027,916			39,547,558
Number of shares of unregistered common stock exchanged for consulting services		10,195
Closing price of common stock		$ 19.37
Consulting services performance period		6 months
Unregistered common stock exchanged for consulting services		$ 197,000				$ 197,000
Compensation expense					$ 2,681,000		$ 2,069,000	$ 4,915,000	$ 3,940,000
General and Administrative [Member]
Subsidiary Sale Of Stock [Line Items]
Compensation expense					1,355,000		$ 1,217,000	2,507,000	$ 2,440,000
General and Administrative [Member] \| Consulting Agreement [Member]
Subsidiary Sale Of Stock [Line Items]
Compensation expense					$ 99,000			$ 99,000
Maximum [Member]
Subsidiary Sale Of Stock [Line Items]
Aggregate offering price of securities										$ 300,000,000
Common Stock [Member]
Subsidiary Sale Of Stock [Line Items]
Restricted stock units vested shares				74,166	74,166
Number of shares of unregistered common stock exchanged for consulting services						10,195
Common Stock [Member] \| Follow-on Public Offering [Member] \| Subsequent Event [Member]
Subsidiary Sale Of Stock [Line Items]
Common stock, shares issued	6,325,000		6,325,000
Proceeds from issuance of common stock net of underwriting discounts, commissions and estimated offering expenses	$ 136,446,000		$ 136,446,000
Underwriting discounts, commission and estimated offering expenses	$ 9,029,000
Closing price of common stock			$ 23.00
Common Stock [Member] \| Underwriter's Over-Allotment [Member] \| Subsequent Event [Member]
Subsidiary Sale Of Stock [Line Items]
Common stock, shares issued	825,000		825,000