Derivative Instruments and Fair Value Accounting - Assets and liabilities Measured at fair value on recurring basis (Details) - Fair value measurements, recurring - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Level 1
Assets:
Cash equivalents	$ 104.4	$ 57.9
Restricted cash	96.3	111.4
Level 1 | Other assets
Assets:
Assets, Fair Value Disclosure	200.7	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
Assets:
Foreign Currency Contract, Asset, Fair Value Disclosure	0.0	1.2
Liabilities [Abstract]
Foreign Currency Contracts, Liability, Fair Value Disclosure	6.7	0.0
Fair Value, Inputs, Level 2 [Member] | Accrued Liabilities [Member]
Liabilities [Abstract]
Financial and Nonfinancial Liabilities, Fair Value Disclosure	58.2	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	$ 51.5	$ 28.0