Annual report pursuant to Section 13 and 15(d)

Income Taxes - Additional Information (Detail)

v3.20.4
Income Taxes - Additional Information (Detail) - USD ($)
 12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Valuation Allowance [Line Items]      
Computed at federal statutory rate 21.00% 21.00% 21.00%
Income taxes receivable $ 0 $ 1,236,000 $ 2,500,000
Deferred State and Local Income Tax Expense (Benefit) (2,660,000) 2,137,000 523,000
Effective Income Tax Rate Reconciliation, Other Adjustments, Amount 1,192,000 (389,000) 285,000
Liabilities for unrecognized tax benefits 0 0  
Deferred Tax Assets, Valuation Allowance 179,006,000 114,939,000  
Income Tax Examination, Penalties and Interest Expense $ 0 $ 0 $ 0
Effective Income Tax Rate Reconciliation, Percent (0.70%) 3.00% 0.20%
Deferred Federal Income Tax Expense (Benefit) $ 1,236,000 $ 1,236,000 $ 2,471,000
Federal (1,236,000) (1,236,000) $ (2,471,000)
Deferred income taxes 0 1,424,000  
Deferred Tax and Other Liabilities, Noncurrent 8,266,000 $ 83,330,000  
Federal      
Valuation Allowance [Line Items]      
Operating Loss Carryforwards 638,600,000    
Federal, State and Local Tax Jurisdictions      
Valuation Allowance [Line Items]      
Deferred Tax Assets, Valuation Allowance $ 179,000,000.0