Annual report pursuant to Section 13 and 15(d)

Income Taxes - Additional Information (Detail)

v3.20.1
Income Taxes - Additional Information (Detail) - USD ($)
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Income Tax Contingency [Line Items]      
Unused operating loss carryforwards for federal tax purposes   $ 201,264,000  
Unused operating loss carryforwards for state tax purposes   $ 217,774,000  
Net operating loss carryforwards, expiration year   2028  
Deferred tax valuation allowance $ 62,136,614 $ 54,152,886 $ 45,146,000
Increase (decrease) in valuation allowance 7,984,000 9,006,000  
Unrecognized tax benefits $ 0 0  
Unrecognized interest   0  
Unrecognized penalties accrued   $ 0  
U.S. federal corporate income tax rate 21.00% 21.00% 34.00%
Tax Cuts and Jobs Act, decrease in deferred tax assets valuation allowance     $ 18,284,538
Research and development credit carry forwards expiration year 2031    
Executive Officer [Member] | Minimum [Member]      
Income Tax Contingency [Line Items]      
Tax Cuts and Jobs Act, compensation deducted     $ 1,000,000