Pension Benefits (Details) (USD $) In Millions, unless otherwise specified	0 Months Ended	12 Months Ended
	Sep. 04, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Defined Benefit Plan Disclosure [Line Items]
Actuarial Gain Recognized in Other Comprehensive Income, Before Tax		$ (106.4)	$ 61.6	$ (29.4)
Defined Contribution Plan, Cost Recognized		7.3	7.3	7.8
Pension Plans, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Pension Plan, Number of Participants and Beneficiaries		9,500
Defined Benefit Pension Plans Active Employees		2,200
Percentage of Compensation, Defined Benefit Plan Employee Contribution		3.00%
Defined Benefit Plan, Contributions by Employer		0	55.0
Defined Benefit Plan, Funded Status of Plan		(91.0)	9.0
Pension Plans, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Contributions by Employer	55.0
Pension Expense Recognized		8.3	29.7	22.5
Actuarial Gain Recognized in Other Comprehensive Income, Before Tax		(102.0)	53.8	(34.8)
Supplemental Employee Retirement Plan, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Funded Status of Plan		31.0	23.3
Pension Expense Recognized		1.8	1.8	1.8
Actuarial Gain Recognized in Other Comprehensive Income, Before Tax		$ (7.0)	$ (1.5)	$ (1.3)