XML 64 R47.htm IDEA: XBRL DOCUMENT v3.20.4
Correction of Immaterial Error - Income Taxes (Details) - USD ($)
Dec. 31, 2020
Dec. 31, 2019
Jan. 01, 2019
Jan. 01, 2018
Quantifying Misstatement in Current Year Financial Statements [Line Items]        
Accumulated deficit $ 525,866,000 $ 516,780,000    
Default In Tax Payments | Cumulative Effect Adjustment        
Quantifying Misstatement in Current Year Financial Statements [Line Items]        
Accumulated deficit     $ 113,000 $ 154,000