Derivative Instruments and Fair Value Accounting - Assets and liabilities Measured at fair value on recurring basis (Details) - Fair Value, Recurring [Member] - USD ($) $ in Millions	Jun. 30, 2020	Dec. 31, 2019
Level 1
Assets:
Cash and Cash Equivalents, Fair Value Disclosure	$ 76.1	$ 57.9
Restricted Cash Fair Value Disclosure	136.9	111.4
Assets, Fair Value Disclosure	213.0	169.3
Fair Value, Inputs, Level 2 [Member]
Assets:
Assets, Fair Value Disclosure	0.0	1.2
Fair Value, Inputs, Level 2 [Member] | Other Assets [Member]
Assets:
Foreign Currency Contract, Asset, Fair Value Disclosure	0.0	1.2
Fair Value, Inputs, Level 2 [Member] | Accrued Liabilities [Member]
Liabilities [Abstract]
Foreign Currency Contracts, Liability, Fair Value Disclosure	1.3	0.0
Financial and Nonfinancial Liabilities, Fair Value Disclosure	53.9	28.0
Level 3
Assets:
Assets, Fair Value Disclosure	0.0
Interest Rate Swap [Member] | Fair Value, Inputs, Level 2 [Member] | Accrued Liabilities [Member]
Liabilities [Abstract]
Derivative Liability	$ 52.6	$ 28.0