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Commitments and Contingencies - Additional Information (Detail) - USD ($)
$ in Millions
3 Months Ended 6 Months Ended
Jun. 30, 2020
Jun. 30, 2020
Derivative Litigation | Positive Outcome of Litigation    
Commitments and Contingencies [Line Items]    
Net proceeds received from settlement agreement becoming effective and final $ 30.2 $ 30.2