Stockholders' Equity - Common Stock - Additional Information (Detail) - USD ($)	1 Months Ended		3 Months Ended			12 Months Ended
	May 06, 2022	Jan. 31, 2021	Mar. 31, 2022	Sep. 30, 2021	Mar. 31, 2021	Dec. 31, 2020	Dec. 31, 2021	Nov. 30, 2017
Sale Of Common Stock [Line Items]
Common stock, shares issued			32,917,901				32,656,480
Proceeds from issuance of common stock, net					$ 13,070,154
Common stock, value of shares issuable								$ 16,000,000.0
Proceeds from issuance of common stock from ATM, net			$ 171,521
Options Granted [Member]
Sale Of Common Stock [Line Items]
Number of stock options granted			450,000		1,315,000
Public Offering [Member]
Sale Of Common Stock [Line Items]
Common stock, shares issued		5,750,000
Shares issued, price per share		$ 2.50
Proceeds from issuance of common stock, net		$ 14,400,000
Proceeds from issuance of common stock net of underwriting discounts and commissions and offering expenses		$ 13,100,000
FBR Sales Agreement [Member]
Sale Of Common Stock [Line Items]
Common stock, shares issued							0
ATM Sales Agreement [Member]
Sale Of Common Stock [Line Items]
Common stock, shares issued			261,421	217,100
Proceeds from issuance of common stock, net				$ 313,000
Proceeds from issuance of common stock from ATM, net			$ 172,000
Common stock , weighted average price per share			$ 0.67	$ 1.47
ATM Sales Agreement [Member] | Maximum [Member]
Sale Of Common Stock [Line Items]
Potential proceeds from issuance of common stock, net						$ 30,000,000
ATM Sales Agreement [Member] | Subsequent Event [Member]
Sale Of Common Stock [Line Items]
Common stock, shares issued	7,198,976
Proceeds from issuance of common stock, net	$ 7,100,000
Common stock , weighted average price per share	$ 1.01