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Goodwill and Intangible Assets - Additional Information (Detail)
$ in Millions
 12 Months Ended
Dec. 31, 2019
USD ($)
Dec. 31, 2018
USD ($)
Dec. 31, 2017
USD ($)
Unit
Schedule Of Goodwill And Other Intangible Assets [Line Items]      
Aggregate amount of goodwill acquired $ 212.8 $ 212.8  
Aggregate amount of impairment 60.7 60.7  
Goodwill, impairment loss 0.0 0.0 $ 4.4
Impairment of intangible assets 0.0 0.0  
Amortization expense of finite life intangible assets 8.5 $ 9.6 $ 11.5
Amortization expense of finite life intangibles for 2020 6.8    
Amortization expense of finite life intangibles for 2021 5.7    
Amortization expense of finite life intangibles for 2022 4.8    
Amortization expense of finite life intangibles for 2023 4.0    
Amortization expense of finite life intangibles for 2024 3.4    
Four Reporting Units [Member]      
Schedule Of Goodwill And Other Intangible Assets [Line Items]      
Number of reporting units | Unit     4
Impairment of intangible assets     $ 2.7
Certain Tradenames [Member]      
Schedule Of Goodwill And Other Intangible Assets [Line Items]      
Finite-lived intangible asset, fair value $ 3.9    
Intangible assets, Useful Life 10 years