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Goodwill and Other Intangible Assets - Additional Information (Detail) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Goodwill And Intangible Assets Disclosure [Abstract]      
Intangibles assets acquired $ 35.2    
Amortization expense of intangible assets $ 13.4 $ 13.0 $ 13.9