Basis of Presentation Pension and Post-Retirement Benefits (Details) - USD ($) $ in Millions		3 Months Ended		9 Months Ended		12 Months Ended
	Jan. 01, 2019	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2019	Dec. 31, 2018
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Right of use assets		$ 430.1		$ 430.1			$ 16.8
Lease liability		440.3		440.3			$ 11.3
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		$ 0.0	$ 0.0	$ 0.0	$ 19.4
Accounting Standards Update 2016-02 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Right of use assets	$ 460.7
Lease liability	483.6
Deferred gain recognized	$ 39.4
Forecast [Member] | Accounting Standards Update 2016-02 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Deferred gain recognized						$ 4.0