Income Tax Deferred Tax Assets And Liabilities (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Operating Loss Carryforwards [Line Items]
Deferred Tax Assets, Net of Valuation Allowance, Current	$ 0.0
Non-current deferred tax assets:
Compensation-related obligations	10.3	$ 22.2
Pension and postretirement benefits	0.0	35.6
Foreign exchange gain/loss	21.0	0.0
Hedging	45.8	0.0
Tax credit carryforwards	23.6	13.0
Tax loss carryforwards	1,214.2	1,004.8
Accrued liabilities and other	28.3	46.1
Other	8.3	7.5
Valuation allowance	(1,077.7)	(901.7)
Total non-current deferred tax assets	273.8	227.5
Non-current deferred tax liabilities:
Fixed assets	69.4	72.5
Partnership investments	898.7	922.0
Foreign exchange gain/loss	0.0	43.0
Deferred Tax Liabilities, Pension and Postretirement Benefits	2.7	0.0
Intangible assets	881.2	800.5
Deferred Tax Liabilities, Derivatives	0.0	13.8
Total non-current deferred tax liabilities	1,852.0	1,851.8
Deferred Tax Assets, Net, Noncurrent	0.0	0.0
Net non-current deferred tax liabilities	$ 1,578.2	$ 1,624.3