Annual report pursuant to Section 13 and 15(d)

Income Taxes - Additional Information (Details)

v3.19.3.a.u2
Income Taxes - Additional Information (Details) - USD ($)
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Income Taxes [Line Items]      
U.S. federal statutory tax rate 21.00% 21.00% 34.00%
Valuation allowance $ 7,455,000 $ 7,659,000  
Cumulative change in ownership percentage 50.00%    
Period for cumulative change in ownership 3 years    
Unrecognized tax benefit that would impact effective tax rate, if recognized $ 9,000    
Income tax interest and penalties accrued 3,000 2,000  
Income tax interest and penalties 1,000 1,000 $ 1,000
California      
Income Taxes [Line Items]      
Net operating loss carry forwards $ 5,700,000    
Net operating loss carry forwards, expire period 2028    
Federal      
Income Taxes [Line Items]      
Net operating loss carry forwards $ 19,000,000    
Net operating loss carry forwards, expire period 2020    
Operating loss carryforward available to offset future taxable income   $ 1,600,000  
Percentage of future taxable income offset by operating loss carryforward 80.00%    
Tax credit carry forwards $ 1,500,000    
Tax credit carry forwards, expire period 2026    
State      
Income Taxes [Line Items]      
Tax credit carry forwards $ 1,500,000