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Stock-Based Compensation - Narrative (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Shares of common stock provided for awarding by the Plan (in shares) 4,800,000    
Number of shares available for issuance (in shares) 2,400,000    
Stock-based compensation expense $ 14.6 $ 9.9 $ 9.0
Income tax benefit related to stock-based compensation expense 2.7 $ 2.6 $ 4.6
Fair value of shares vested $ 13.3    
Restricted Stock | Minimum      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Award vesting period 1 year    
Restricted Stock | Maximum      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Award vesting period 15 years    
Restricted share awards      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Unrecognized compensation expense related to restricted share awards $ 24.6    
Weighted average recognition period 2 years 10 months 24 days    
Performance units | Minimum      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Percentage of target grant potentially issuable depending on achievement of certain specified goals 0.00%    
Performance units | Maximum      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Percentage of target grant potentially issuable depending on achievement of certain specified goals 200.00%