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Stock-Based Compensation (Additional Information) (Details)
$ in Millions
3 Months Ended 60 Months Ended
Mar. 31, 2017
USD ($)
offering_periods
Mar. 31, 2016
USD ($)
Mar. 31, 2017
shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Cash received from exercise of stock options $ 0.8    
Employee Stock Option      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Stock options, contractual term (years) 10 years    
Stock options, grants in period, gross | shares     0
Options exercised, total intrinsic value $ 1.1    
Performance-Based Restricted Stock      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Restricted stock award program, measurement period (years) 3 years    
Expected dividend yield (percent) 0.00%    
Compensation expense (income) $ (0.1) $ 0.7  
Performance-Based Restricted Stock | Minimum      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Restricted stock award program, awarded shares as a percentage of the original award amount (percent) 0.00%    
Performance-Based Restricted Stock | Maximum      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Restricted stock award program, awarded shares as a percentage of the original award amount (percent) 200.00%    
Time Based Restricted Stock      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Compensation expense (income) $ 1.0 1.2  
Employee Stock Purchase Plan      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Compensation expense (income) $ 0.1 $ 0.1  
Employee stock purchase plan, number of offering (offering period) | offering_periods 2    
Employee stock purchase plan, offering period (months) 6 months    
Employee stock purchase plan, purchase price discount (percent) 15.00%