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Common Stock - Additional Information (Detail) - USD ($)					12 Months Ended
	Feb. 25, 2021	Jul. 16, 2020	Mar. 27, 2020	Mar. 12, 2019	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Changes In Equity And Comprehensive Income Line Items [Line Items]
Proceeds from issuance of common stock in public offering, net					$ 64,815,379	$ 48,156,072
Common stock, par or stated value per share					$ 0.0001	$ 0.0001
Pre-Funded Warrants [Member]
Changes In Equity And Comprehensive Income Line Items [Line Items]
Number of securities called by warrants or rights					0
Exchange Warrants [Member]
Changes In Equity And Comprehensive Income Line Items [Line Items]
Number of securities called by warrants or rights	1,000,000
Common stock, par or stated value per share	$ 0.0001
Number Of Warrants Exercised					0
Common stock exchanged for pre-funded warrants	1,000,000
Ownership percentage	9.99%
Per share exercise price	$ 0.0001
Public Offering [Member]
Changes In Equity And Comprehensive Income Line Items [Line Items]
Gross proceeds from offering including exercise of underwriter's option		$ 132,200,000
Public Offering [Member] \| Pre-Funded Warrants [Member]
Changes In Equity And Comprehensive Income Line Items [Line Items]
Purchase price of warrants issued		$ 22.9999
Ownership percentage on exercise of warrants without notice, minimum		4.99%
Ownership percentage on exercise of warrants with notice, maximum		19.99%
Notice period to increase ownership percentage on exercise of warrants		61 days
Per share exercise price		$ 0.0001
Public Offering [Member] \| Common Stock [Member]
Changes In Equity And Comprehensive Income Line Items [Line Items]
Public offering price, per share		$ 23.00
Shares of common stock sold		3,369,564
Public Offering [Member] \| Common Stock [Member] \| Pre-Funded Warrants [Member]
Changes In Equity And Comprehensive Income Line Items [Line Items]
Number of securities called by warrants or rights		1,630,436
Over-Allotment Option [Member] \| Common Stock [Member]
Changes In Equity And Comprehensive Income Line Items [Line Items]
Proceeds from issuance of common stock in public offering, net		$ 124,000,000.0
Shares of common stock sold		750,000
At-The-Market Offering [Member] \| Equity Distribution Agreement [Member] \| JMP Securities LLC [Member]
Changes In Equity And Comprehensive Income Line Items [Line Items]
Proceeds from issuance of common stock in public offering, net						$ 48,200,000
Common stock, par or stated value per share			$ 0.0001
Aggregate offering price			$ 18,900,000
Shares of common stock sold					0	5,594,455
At-The-Market Offering [Member] \| Equity Distribution Agreement [Member] \| JMP Securities LLC [Member] \| Maximum [Member]
Changes In Equity And Comprehensive Income Line Items [Line Items]
Aggregate offering price			$ 50,000,000.0
At-The-Market Offering [Member] \| Equity Distribution Agreement [Member] \| Piper Sandler company and evercore group limited liability company and B Riley Securities inc [Member]
Changes In Equity And Comprehensive Income Line Items [Line Items]
Common stock available to be sold					$ 58,000,000.0
Deferred Offering Costs					100,000
Proceeds from issuance of common stock in public offering, net					$ 64,800,000
Common stock, par or stated value per share	$ 0.0001
Aggregate offering price	$ 125,000,000.0
Shares of common stock sold					4,800,454
Issuance costs					$ 100,000
Registered Direct Offering [Member]
Changes In Equity And Comprehensive Income Line Items [Line Items]
Proceeds from issuance of common stock in public offering, net				$ 12,700,000
Issuance of transaction date				Mar. 12, 2019
Common units outstanding				4,361,370
Warrant expiration period				5 years
Deemed Dividend							$ 452,925
Registered Direct Offering [Member] \| Maximum [Member]
Changes In Equity And Comprehensive Income Line Items [Line Items]
Per share exercise price				$ 4.1798
Registered Direct Offering [Member] \| Minimum [Member]
Changes In Equity And Comprehensive Income Line Items [Line Items]
Per share exercise price				$ 2.7568
Registered Direct Offering [Member] \| Common Units [Member]
Changes In Equity And Comprehensive Income Line Items [Line Items]
Number of securities called by warrants or rights				0.70
Public offering price per share				$ 3.21
Per share exercise price				$ 3.21
Registered Direct Offering [Member] \| Prefunded Units [Member]
Changes In Equity And Comprehensive Income Line Items [Line Items]
Number of securities called by warrants or rights				0.70
Public offering price per share				$ 3.20
Per share exercise price				3.21
Per share exercise price				$ 0.01