Principles Of Consolidation (Claims and Insurance) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Workers' Compensation [Member]
LIability For Unpaid Claims And Claim Adjustment Expense, Adjustment Of Opening Balance [Roll Forward]
Undiscounted amount	$ 347.0	$ 390.1
Estimated settlement cost	94.3	89.2
Claim payments, net of recoveries	(114.5)	(115.6)
Change in estimated settlement cost for older claim years	12.3	(16.7)
Undiscounted amount	339.1	347.0
Discounted settlement cost estimate	311.3
Property Damage and Liability Claims [Member]
LIability For Unpaid Claims And Claim Adjustment Expense, Adjustment Of Opening Balance [Roll Forward]
Undiscounted amount	68.8	65.1
Estimated settlement cost	39.0	36.7
Claim payments, net of recoveries	(40.8)	(24.3)
Change in estimated settlement cost for older claim years	8.0	(8.7)
Undiscounted amount	75.0	68.8
Discounted settlement cost estimate	74.5
Total [Member]
LIability For Unpaid Claims And Claim Adjustment Expense, Adjustment Of Opening Balance [Roll Forward]
Undiscounted amount	415.8	455.2
Estimated settlement cost	133.3	125.9
Claim payments, net of recoveries	(155.3)	(139.9)
Change in estimated settlement cost for older claim years	20.3	(25.4)
Undiscounted amount	414.1	415.8
Discounted settlement cost estimate	385.8
Cargo Claims And Other Insurance Related Amounts [Member]
LIability For Unpaid Claims And Claim Adjustment Expense, Adjustment Of Opening Balance [Roll Forward]
Undiscounted amount	$ 20.8	$ 15.6