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Summary of Significant Accounting Policies - Additional Information 3 (Detail) - USD ($)
3 Months Ended 6 Months Ended
Jun. 30, 2020
Jun. 30, 2019
Jun. 30, 2020
Jun. 30, 2019
Dec. 31, 2019
Accounting Policies [Abstract]          
Federal statutory rate 21.00% 21.00% 21.00% 21.00%  
Derivative instruments $ (6,780,000) $ 0 $ (6,780,000) $ 0 $ 4,351,000