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Goodwill and Intangible Assets - Additional Information (Detail) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Goodwill [Line Items]      
Amortization expense associated with identifiable intangible assets $ 3.9 $ 0.8 $ 0.4
Estimated total amortization expense 2021 5.7    
Estimated total amortization expense 2022 6.9    
Estimated total amortization expense 2023 7.9    
Estimated total amortization expense 2024 6.7    
Estimated total amortization expense 2025 5.7    
Indefinite-lived Intangible Assets [Member]      
Goodwill [Line Items]      
Goodwill and intangible assets with indefinite lives $ 147.4 $ 146.9