Related Party Transactions (Details) - Equity Method Investee - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Related Party Transaction [Line Items]
Trade receivables	$ 100.0		$ 100.0		$ 98.4
Trade payables	(16.7)		(16.7)		(121.8)
Net trade receivables/(payables)	83.3		83.3		(23.4)
Note receivables	129.5		129.5		$ 140.9
Revenue	60.2	$ 33.0	152.7	$ 68.4
Expenses	$ 2.6	$ 22.3	$ 6.0	$ 62.9

Amount for accounts payable to related parties.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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