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Goodwill and Other Intangible Assets - Additional Information (Details) - USD ($)
$ in Millions
3 Months Ended
Mar. 31, 2019
Mar. 31, 2018
Goodwill and Intangible Assets Disclosure [Abstract]    
Amortization expense $ 4.4 $ 3.8
Annual Future Amortization Expense    
Anticipated future amortization expense for 2019 13.3  
Anticipated future amortization expense for 2020 14.6  
Anticipated future amortization expense for 2021 13.8  
Anticipated future amortization expense for 2022 13.3  
anticipated future amortization expense for 2023 $ 12.7