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Goodwill and Other Identifiable Intangible Assets - Additional Information (Detail) - USD ($)
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Goodwill and Intangible Assets Disclosure [Abstract]      
Impairment charges, goodwill $ 0 $ 0 $ 0
Amortization 28,400,000 31,700,000 34,900,000
Impairment charges, related to trade names $ 0 $ 0 $ 0