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Financial Derivatives - Additional Information (Detail) - USD ($)
6 Months Ended 12 Months Ended
Jun. 30, 2021
Dec. 31, 2020
Derivative Instruments And Hedging Activities Disclosure [Abstract]    
Maximum amount of loss due to credit risk $ 600,000 $ 300,000
Total net settlement amount asset positions 500,000 300,000
Total net settlement amount liability positions $ 1,000,000.0 $ 2,400,000