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Stock Based Compensation - Additional Information (Details) - USD ($)
$ in Millions
12 Months Ended
Feb. 05, 2019
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
May 30, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Stock-based compensation, capitalized amount   $ 0.0 $ 0.0 $ 0.0  
Vesting period   3 years      
Minimum          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Stock distribution period   30 days      
Maximum          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Stock distribution period   15 months      
Restricted Stock Units          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Granted (in shares)   67,000      
Total fair value of shares vested   $ 4.0 4.0 3.0  
Unrecognized compensation cost (less than)   $ 4.0      
Weighted-average period   1 year 8 months 19 days      
Accrued dividend equivalents   $ 1.0 1.0 1.0  
Performance Condition          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Granted (in shares)   145,000      
Vesting period   3 years      
Total fair value of shares vested   $ 14.0 $ 12.0 $ 13.0  
Unrecognized compensation cost (less than)   $ 4.0      
Weighted-average period   1 year 1 month 2 days      
Historical volatility, stock price, period   3 years      
Expected term   3 years      
2017 Omnibus Equity Compensation Plan          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Total shares authorized for grant (in shares)         7,200,000
Shares available for grant (in shares)   6,800,000      
2007 Omnibus Equity Compensation Plan | Stock Options          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Granted (in shares)   0 0 0  
Vesting period   3 years      
Total fair value of shares vested   $ 1.0 $ 1.0 $ 2.0  
Unrecognized compensation cost (less than)   $ 0.0      
Weighted-average period   1 year      
2007 Omnibus Equity Compensation Plan | Stock Options | Minimum          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Vesting period   1 year      
2007 Omnibus Equity Compensation Plan | Restricted Stock Units | Minimum          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Vesting period   1 year 1 year 1 year  
2007 Omnibus Equity Compensation Plan | Restricted Stock Units | Maximum          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Vesting period   3 years 3 years 3 years  
Employee Stock Purchase Plan          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Shares available for grant (in shares)   1,800,000      
Lesser of fair market value 85.00%        
Stock issuable (in shares)   2,000,000.0      
Shares issued (in shares)   88,000 95,000 93,000