Stock-Based Compensation - Additional Information (Detail) - USD ($)		6 Months Ended
Mar. 29, 2019	Jun. 30, 2019
2019 Employee Stock Purchase Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock reserved for issuance	403,500
Percent of payroll deductions	10.00%
Percentage of discount from fair market value of common stock on first or last trading day of offering period	85.00%
Stock Options [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock option vesting Period		4 years
Stock option expiration Period		10 years
Unrecognized compensation cost, stock options		$ 1,579,524
Unrecognized stock-based compensation expense, period for recognition		3 years 4 months 20 days
Number of Stock Options, Granted		618,000
Stock options granted, weighted-average exercise price		$ 2.76
Weighted-average grant date fair value of stock options granted		$ 2.09
Restricted Stock [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized stock-based compensation expense, period for recognition		3 years 5 months 1 day
Unvested restricted stock, shares		323,262
Unrecognized compensation expense		$ 990,288
Common stock issued as result of vesting of restricted stock		71

Aggregate number of common shares reserved for future issuance.

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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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The highest percentage of annual salary that an employee is permitted to utilize with respect to the plan.

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

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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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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Number of shares issued during the period related to Restricted Stock Awards, net of any shares forfeited.

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