Stockholders' Equity - Common Stock - Additional Information (Detail) - USD ($)	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019	Nov. 30, 2017
Options Granted [Line Items]
Common stock, shares issued	26,332,122		24,431,914
Proceeds from issuance of common stock, net	$ 3,309,116	$ 5,800,201
Warrants converted to purchase of common stock	871,682
Issuance of common stock from warrant exercise	381,625
Issuance of common stock from stock option exercise, shares	4,237
Exercise Price	$ 0.62
Options Granted [Member]
Options Granted [Line Items]
Number of stock options granted	1,172,000
Options Granted [Member] | Gimoti [Member]
Options Granted [Line Items]
Number of stock options not begin vesting	437,500
Maximum [Member]
Options Granted [Line Items]
Weighted average exercise price of warrants	$ 3.12
Minimum [Member]
Options Granted [Line Items]
Weighted average exercise price of warrants	$ 2.41
FBR Sales Agreement [Member]
Options Granted [Line Items]
Common stock, shares issued	1,395,855	6,804,381
Common stock, weighted average price per share	$ 2.42	$ 0.87
Proceeds from issuance of common stock, net	$ 3,300,000	$ 5,800,000
FBR Sales Agreement [Member] | Maximum [Member]
Options Granted [Line Items]
Common stock, value of shares issuable				$ 16,000,000