Pension and Other Post-Retirement Benefits Narrative (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Amortization period for pension plan actuarial losses (in years)			20 years
Pension plan required minimum contributions, 2015			$ 10.3
Pension plan required minimum contributions, 2016			14.3
Pension plan required minimum contributions, 2017			15.3
Pension plan required minimum contributions, 2018			17.0
Pension plan required minimum contributions, 2019			18.3
Pension plan required minimum contributions, thereafter			56.4
Other Postretirement Benefit Plans, Defined Benefit
Defined Benefit Plan Disclosure [Line Items]
Aggregate expense of other postretirement benefit plans	$ 0.4	$ 0.5	$ 0.9	$ 0.9