Accrued share based compensation expense.

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Percentage of voting power.

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Share based compensation arrangement by share based payment award exercise price of common stock percent.

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- Definition

Share-based compensation arrangement by share-based payment award, increase in number of shares.

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No definition available.

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- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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- Definition

Aggregate number of common shares reserved for future issuance.

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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 nonvested award under share-based payment arrangement. Excludes share and unit options.

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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

Discount rate from fair value on offering date that participants pay for shares.

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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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 equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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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

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

Maximum number of shares that may be issued in accordance with the plan as a proportion of outstanding capital stock.

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No definition available.

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Number of shares issued under share-based payment arrangement.

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- Definition

Percentage of vesting of award under share-based payment arrangement.

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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

Purchase price of common stock expressed as a percentage of its fair value.

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No definition available.

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Stock-Based Compensation - Additional Information (Details) - USD ($)	1 Months Ended	3 Months Ended		6 Months Ended
	Dec. 31, 2018	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Jan. 01, 2020	Dec. 31, 2019
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares reserved for issuance		6,385,684		6,385,684			5,296,732
Accrued share based compensation expense		$ 100,000	$ 0	$ 100,000	$ 0
Options granted			0	804,975
Restricted Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expects to recognize over a remaining weighted-average period				1 month 6 days
Restricted Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense related to awards				$ 100,000
Unrecognized stock-based compensation		$ 0		$ 0
Shares cancelled		0		0
Executive Officer \| Restricted Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period	2 years
Issued of common stock	116,518
Grant date fair value per share	$ 1.39
Shares vested				58,259
Board of Directors \| Restricted Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Issued of common stock		1,828		1,828
Grant date fair value per share		$ 51.30		$ 51.30
2018 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of exercise price of stock option on estimated fair value of shares				110.00%
Vesting period				3 years
Shares reserved for issuance		4,384,000		4,384,000
Increase in number of shares						964,487
Outstanding stock percent				4.00%
Shares available for issuance		2,855,052		2,855,052
2018 Plan \| Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Term of options				10 years
Increase in number of shares		8,768,800		8,768,800
2018 Plan \| Share-based Compensation Award, Tranche One
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting percentage				25.00%
Vesting period				1 year
2018 Plan \| 10% Stockholder \| Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Term of options				5 years
2018 Plan \| 10% Stockholder \| Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of voting power				10.00%
ESPP
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Increase in number of shares						241,121
Outstanding stock percent				1.00%
Shares available for issuance		497,826		497,826			280,000
Percentage of exercise price of stock option on estimated fair value of shares				85.00%
Issued of common stock				23,295
ESPP \| Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Increase in number of shares		560,000		560,000
Discount rate				15.00%