Preferred Stock, Common Stock and Stockholders' Equity - Common Stock - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Feb. 29, 2020	Dec. 31, 2017	Nov. 30, 2017
Sale Of Stock [Line Items]
Common stock, shares outstanding	24,431,914	17,427,533
Shareholders voting power description	Each share of common stock is entitled to one vote. The holders of the common stock are also entitled to receive dividends whenever funds are legally available and when declared by the board of directors of the Company.
Dividends declared on common stock	$ 0
Shares of common stock subject to Registration Rights	1,509,789
Common stock, shares issued	24,431,914	17,427,533
Proceeds from issuance of common stock, net	$ 6,106,922	$ 4,618,297
FBR Sales Agreement [Member]
Sale Of Stock [Line Items]
Common stock, shares issued	7,004,381	1,985,054		0
Common stock , weighted average price per share	$ 0.89	$ 2.38
Proceeds from issuance of common stock, net	$ 6,100,000	$ 4,600,000
FBR Sales Agreement [Member] | Maximum [Member]
Sale Of Stock [Line Items]
Common stock, value of shares issuable					$ 16,000,000
FBR Sales Agreement [Member] | Subsequent Event [Member]
Sale Of Stock [Line Items]
Common stock, shares issued			0