One time share-based compensation cumulative reversal for forfeitures of outstanding equity awards.

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- Definition

Share based compensation arrangement by share based payment award number of additional shares authorized annual percentage.

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- Definition

Share-based compensation arrangement by share-based payment award vesting date.

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- Definition

Shares issued for special retention grant.

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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 option under share-based payment arrangement.

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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

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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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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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

Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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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

Weighted average grant-date fair value of non-vested options outstanding.

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No definition available.

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- Definition

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

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Stock-Based Compensation - Additional Information (Detail) - USD ($)	1 Months Ended		3 Months Ended	12 Months Ended
	May 31, 2019	Mar. 31, 2017	Dec. 31, 2019	Dec. 31, 2019	Dec. 31, 2018	Jan. 01, 2020	Jan. 01, 2019	Dec. 31, 2017
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Options to purchase common stock, granted				4,666,728	1,615,200
Aggregate intrinsic value of option outstanding			$ 2,866	$ 2,866	$ 142,788			$ 2,738,704
Stock options exercised				0	52,099
Stock options exercised, intrinsic value					$ 139,108
Unrecognized compensation cost related to stock options			$ 2,309,337	$ 2,309,337
Weighted-average fair value of options granted			$ 1.11	$ 1.11	$ 2.22
Chief Executive Officer and Chief Financial and Business Officer [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
One-time stock-based compensation cumulative reversal for forfeitures of outstanding equity awards			$ 1,051,735	$ 1,100,000
Stock Option [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period				48 months
Compensation expense				$ 1,085,842	$ 2,982,173
Weighted average period expected to be recognized				2 years 3 months 21 days
Restricted Stock [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Compensation expense				$ 0	$ 449,689
2017 Stock Option and Incentive Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock shares available for issuance		4,600,000					1,623,520
Percentage applied to the outstanding shares as annual increase in number of shares authorized for issuance		4.00%
2017 Stock Option and Incentive Plan [Member] \| Stock Option [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock shares available for issuance			1,983,093	1,983,093	2,959,562
Term of options to be granted				10 years
Options to purchase common stock, granted				4,666,728	1,615,200
Shares issued for special retention grant	2,419,050
2017 Stock Option and Incentive Plan [Member] \| Stock Option [Member] \| One-year Anniversary [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting percentage				25.00%
2017 Stock Option and Incentive Plan [Member] \| Stock Option [Member] \| First Installment [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting percentage	50.00%
Option, vesting date	Jun. 30, 2020
2017 Stock Option and Incentive Plan [Member] \| Stock Option [Member] \| Second Installment [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting percentage	50.00%
Option, vesting date	Jun. 30, 2021
2017 Stock Option and Incentive Plan [Member] \| Subsequent Event [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock shares available for issuance						1,623,520