Stock Compensation - Additional Information (Detail) - USD ($)	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Proceeds from exercise of stock options	$ 26,149	$ 89,350
Stock options to purchase shares of common stock	12,201,668
Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock unit granted	0	0
Options granted, expiration Period	7 years	7 years
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense related to non-vested stock compensation awards granted under the Plan	$ 1,500,000
Expected remaining weighted average vesting period	2 years 8 months 1 day
Non-cash stock-based compensation expense	$ 135,679	$ 0
Common stock granted	0	0
Options to Purchase Common Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of stock options exercised	11,666	65,000
Proceeds from exercise of stock options	$ 26,149	$ 89,350
Common stock unit granted	735,000	207,000
Unrecognized compensation expense related to non-vested stock compensation awards granted under the Plan	$ 10,400,000
Expected remaining weighted average vesting period	2 years 2 months 23 days
Non-cash stock-based compensation expense	$ 1,383,672	$ 933,411
Stock option vested during the period	854,831	984,164
Stock options to purchase shares of common stock	6,687,980

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

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