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Stockholders' Equity - Additional Information (Detail) - USD ($)
 1 Months Ended 3 Months Ended 6 Months Ended
Apr. 11, 2019
Feb. 28, 2018
Jan. 31, 2018
Jun. 30, 2019
Jun. 30, 2018
Jun. 30, 2019
Jun. 30, 2018
Feb. 15, 2018
Stockholders Equity [Line Items]                
Gross proceeds on sale of shares of common stock     $ 10,000,000       $ 1,100,000  
Aggregate commission rate     3.00%          
Common stock, shares issued and sold (in shares) 5,261,250 5,000,000   0 0 0 375,000  
Issuance costs incurred             $ 237,403  
Warrants to purchase common stock (in shares)   3,500,000.0   30,333   30,333    
Amount recorded to additional paid in capital as a result of triggered anti-diluted provisions       $ 789,594 $ 0 $ 789,594 $ 0  
Warrants exercised (in shares)           0 0  
Underwritten Offering                
Stockholders Equity [Line Items]                
Common stock, shares issued and sold (in shares) 686,250 220,500            
Warrants to purchase common stock (in shares)   525,000            
Underwriters overallotment option to purchase additional shares of common stock and warrants period 30 days 30 days            
Underwriters option to purchase additional shares (in shares)   750,000            
Gross proceeds from offering of common stock and warrants $ 5,800,000 $ 10,300,000            
Proceeds received in public offering, net of underwriting discounts and offering expenses $ 5,200,000 $ 9,400,000            
Exercise price (in usd per share)   $ 3.00            
Public Stock Offering                
Stockholders Equity [Line Items]                
Common stock, shares issued and sold (in shares) 4,575,000              
Public offering price in the Offering (in usd per share) $ 1.10 $ 0.70            
Warrants Expiring on February 15, 2023                
Stockholders Equity [Line Items]                
Exercise price (in usd per share) $ 0.98     $ 0.98   $ 0.98    
Accounting Standards Update 2017-11                
Stockholders Equity [Line Items]                
Estimated fair value of warrants recorded in equity               $ 3,000,000