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Goodwill and Other Intangible Assets - Additional Information (Detail) - USD ($)
3 Months Ended 9 Months Ended
Sep. 30, 2020
Sep. 30, 2019
Sep. 30, 2020
Sep. 30, 2019
Goodwill and Intangible Assets Disclosure [Abstract]        
Impairment of goodwill     $ 0  
Amortization expense for intangible assets $ 13,700,000 $ 12,900,000 $ 40,800,000 $ 38,000,000.0