XML 95 R75.htm IDEA: XBRL DOCUMENT v3.20.4
Income Taxes - Narrative (Details) - USD ($)
 3 Months Ended 12 Months Ended
Dec. 31, 2019
Sep. 30, 2019
Jun. 30, 2019
Mar. 31, 2019
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Operating Loss Carryforwards [Line Items]              
Income tax benefit $ (87,764) $ 0 $ (106,771) $ (62,800) $ 0 $ (257,335) $ 2,169,811
Tax benefits expired         10,200,000    
Unrecognized tax benefits that would impact effective tax rate $ 9,900,000       10,900,000 $ 9,900,000 8,300,000
Federal              
Operating Loss Carryforwards [Line Items]              
Net operating loss carryforwards that will expire due to IRC Section 382 limitations         566,200,000    
Net operating loss carryforwards             $ 270,300,000
Federal | Research Tax Credit Carryforward              
Operating Loss Carryforwards [Line Items]              
Tax credit carryforward amount         19,800,000    
California              
Operating Loss Carryforwards [Line Items]              
Net operating loss carryforwards that will expire due to IRC Section 382 limitations         68,600,000    
Pennsylvania              
Operating Loss Carryforwards [Line Items]              
Net operating loss carryforwards that will expire due to IRC Section 382 limitations         75,300,000    
State              
Operating Loss Carryforwards [Line Items]              
Net operating loss carryforwards         143,900,000    
State | Research Tax Credit Carryforward              
Operating Loss Carryforwards [Line Items]              
Tax credit carryforward amount         $ 3,200,000