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Income Taxes - Additional Information (Detail) - USD ($)
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Income Tax Disclosure [Abstract]      
Statutory federal income tax rate 21.00% 21.00% 21.00%
Valuation allowance $ 0 $ 0  
Liability for uncertain tax positions, current 0    
Unrecognized tax benefits $ 0