XML 80 R67.htm IDEA: XBRL DOCUMENT v3.8.0.1
Employee Benefits - Postretirement Plan and Summary Information for All Defined Benefit Plans (Details) - USD ($)
$ in Millions
 1 Months Ended 12 Months Ended
Apr. 30, 2006
Dec. 31, 2017
Dec. 31, 2016
Dec. 31, 2015
Supplemental Executive Retirement Plans        
Summary of benefit payments under the Company's various defined benefit plans, which reflect expected future employee service, as appropriate, expected to be paid in the future periods        
2018   $ 1.2    
2019   1.1    
2020   13.5    
2021   1.1    
2022   8.3    
2023-2027   4.6    
Amounts in accumulated other comprehensive loss that are expected to be recognized as components of net periodic benefit cost during 2018        
Actuarial loss   1.0    
Total   1.0    
Defined Benefit Plans        
Summary of benefit payments under the Company's various defined benefit plans, which reflect expected future employee service, as appropriate, expected to be paid in the future periods        
2018   4.2    
2019   4.4    
2020   4.5    
2021   4.7    
2022   4.9    
2023-2027   27.4    
Amounts in accumulated other comprehensive loss that are expected to be recognized as components of net periodic benefit cost during 2018        
Actuarial loss   1.4    
Prior service cost   0.3    
Total   $ 1.7    
Supplemental Bonus Plan        
Stock-Based Compensation        
Number of shares of the entity to be contributed to the plan as a result of acquisition 258,006      
Share liability to the plan to be settled in cash   75,379    
Cash equivalent of share liability to the plan   $ 6.5    
Expense (income) from mark to market adjustment   $ 0.6 $ 2.1 $ (0.2)