Pension and Other Post Retirement Benefits - Narrative (Details) - Defined Benefit Pension [Member] - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Settlement	$ (2.1)	$ 0.0	$ (2.1)	$ (0.1)
Defined Benefit Plan, Service Cost	$ 2.0	$ 1.6	$ 6.1	$ 4.9