Annual report pursuant to Section 13 and 15(d)

Subsequent Events - Additional Information (Detail)

v3.10.0.1
Subsequent Events - Additional Information (Detail) - USD ($)
12 Months Ended
Feb. 27, 2019
Dec. 31, 2018
Subsequent Event [Line Items]    
Proceeds from issuance of common stock   $ 38,846,815
Subsequent Event [Member]    
Subsequent Event [Line Items]    
Proceeds from issuance of common stock $ 23,300,000  
Underwriter’s discount and offering expenses $ 1,700,000