Income Taxes Income Taxes - Operating Loss Carryforwards (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Operating Loss Carryforwards [Line Items]
Net operating loss and capital loss carryforwards	$ 74.6	$ 71.5
State Operating Loss Carryforwards	791.1
Deferred tax liability, unremitted foreign earnings	98.5	38.5
U.S. Federal
Operating Loss Carryforwards [Line Items]
Foreign tax credit carryforwards	139.5
Non-U.S. Tax Jurisdiction
Operating Loss Carryforwards [Line Items]
Operating Loss Carryforwards	168.9
Operating Loss Carryforwards subject to expiration	110.0
Operating Loss Carryforwards not subject to expiration	58.9
Operating Loss Carryforwards valuation allowance	88.0
Net operating loss and capital loss carryforwards	168.9
Non-U.S. income tax holidays	31.0	$ 25.5
State and Local Jurisdiction
Operating Loss Carryforwards [Line Items]
Operating Loss Carryforwards valuation allowance	779.2
Deferred Tax Assets, Tax Credit Carryforwards, Other	19.7
Tax Credit Carryforward, Valuation Allowance	$ 19.7