Accounting Changes Pension and Post-Retirement Benefits (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Jan. 01, 2019
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification	$ 0.0	$ (0.2)	$ 0.0
Additions to Other Assets, Amount				$ 470.0
Operating Lease, Liability				480.0
Deferred Tax Assets, Deferred Gain on Sale Leaseback Transaction	4.0			$ 4.0
Reclassification out of Accumulated Other Comprehensive Income [Domain]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification	$ 19.4	$ 0.1	$ 0.0