XML 60 R49.htm IDEA: XBRL DOCUMENT v3.7.0.1
Employee Benefit Plans and Other Postretirement Benefits (Details) - USD ($)
 3 Months Ended
Mar. 31, 2017
Mar. 31, 2016
Pension Contributions [Abstract]    
Expected contribution to qualified plans (at least) $ 8,000,000  
Pension Plans    
Defined Benefit Plan Disclosure [Line Items]    
Service cost 6,100,000 $ 6,100,000
Interest cost 10,400,000 10,200,000
Expected return on plan assets (13,500,000) (12,400,000)
Net amortization of unrecognized amounts, Prior service cost 1,500,000 1,400,000
Net amortization of unrecognized amounts, Actuarial loss 1,900,000 1,400,000
Net periodic benefit cost 6,400,000 6,700,000
Pension Contributions [Abstract]    
Contributions to pension plan 3,700,000  
Postretirement Plans    
Defined Benefit Plan Disclosure [Line Items]    
Service cost 100,000 200,000
Interest cost 100,000 200,000
Net amortization of unrecognized amounts, Actuarial loss 0 (200,000)
Net periodic benefit cost $ 200,000 $ 200,000