Annual report pursuant to Section 13 and 15(d)

Stock-Based Compensation - Narrative (Details)

v3.8.0.1
Stock-Based Compensation - Narrative (Details) - USD ($)
$ / shares in Units, $ in Millions
12 Months Ended
Jun. 02, 2017
Dec. 31, 2017
Dec. 31, 2016
Apr. 30, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Excess tax benefit   $ 0.5 $ 0.3  
Performance Share Awards (PSAs)        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Performance condition based on earnings before interest, taxes, depreciation and amortization   75.00%    
Performance condition based on cumulative free cash flow   25.00%    
Restricted Stock Units (RSUs)        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Award vesting period   3 years    
Number of shares accounted for as liability awards (in shares)   231,600 362,800  
Weighted-average grant date fair value of PSUs and RSUs (in dollars per share)     $ 13.73  
Restricted Stock Units (RSUs) | Year One        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Award vesting percentage   33.33%    
Restricted Stock Units (RSUs) | Year Two        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Award vesting percentage   33.33%    
Restricted Stock Units (RSUs) | Year Three        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Award vesting percentage   33.33%    
Modified Performance Share Units (PSUs)        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Award requisite service period completed at modification   2 years    
Award requisite service period   3 years    
Performance Share Units that may be settled in cash        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Number of shares accounted for as liability awards (in shares)   5,228 3,369  
Restricted Stock Units that may be settled in cash        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Number of shares accounted for as liability awards (in shares)   5,676 7,646  
Grant date fair value of RSUs     $ 1.2  
PSAs and PSUs        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Number of shares accounted for as liability awards (in shares)   892,700 801,900  
Weighted-average grant date fair value of PSUs and RSUs (in dollars per share)     $ 12.73  
Performance Shares, Performance Share Units and Restricted Stock Units        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Total unrecognized compensation expense   $ 2.9    
Weighted average period   1 year 7 months    
2016 LTIP Plan        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Number of shares available for grant (in shares)   3,313,537    
2016 Directors' Plan        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Number of shares available for grant (in shares)   312,651    
2016 Directors' Plan | Restricted Stock Units (RSUs)        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Award vesting period   1 year    
Number of shares accounted for as liability awards (in shares)   188,868 163,040  
Common Stock | 2016 LTIP Plan        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Number of shares authorized (in shares) 7,600,000.0     5,500,000
Number of additional shares authorized (in shares) 2,100,000      
Common Stock | 2016 Directors' Plan        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Number of shares authorized (in shares)       600,000