Percentage of internal rate of return on investment .

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- Definition

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

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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 noncash expense for share-based payment arrangement.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
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- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued 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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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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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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No definition available.

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- Definition

Number of shares authorized for issuance under share-based payment arrangement.

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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

Gross number of share options (or share units) granted during the period.

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No definition available.

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- Definition

Number of options outstanding, including both vested and non-vested options.

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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Number of share options (or share units) exercised during the current period.

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Equity Incentive Plan - Additional Information (Detail) - USD ($)	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock option exercised	0	0
Stock-based compensation	$ 825,000	$ 910,000
Non Employee Director [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation		$ 500,000
Stock award, Granted		5,556
Performance Based Vesting Stock Option [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expiration period	10 years
Weighted average fair value granted	$ 0	$ 37.16
Stock option outstanding	0
Performance Based Vesting Stock Option [Member] \| Minimum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Internal rate of return on investment	70.00%
Restricted Stock Units [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation	$ 0
Stock award, Granted	1,000,000
Stock award, outstanding	1,000,000
Restricted Stock Units [Member] \| Non Employee Director [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period	3 years
Stock award, Granted	50,000
2019 Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock options authorized under plan	7,500,000
Common stock options available for issuance	2,479,781
Stock award, Granted	3,475,045
Stock award, outstanding	3,970,219		514,710
2019 Plan [Member] \| Time Based Vesting Stock Option [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period	3 years
Expiration period	10 years
Weighted average fair value granted	$ 2.24
Stock-based compensation	$ 800,000
Unrecognized stock-based compensation expense	$ 8,100,000
Unrecognized stock-based compensation expense, period	3 years
2016 Plan [Member] \| Time Based Vesting Stock Option [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period	5 years
Expiration period	10 years
Weighted average fair value granted	$ 0	$ 37.16
Stock-based compensation	$ 0	$ 900,000