Financial Instruments - Balance Sheet (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2017	Dec. 31, 2016
Derivatives, Fair Value [Line Items]
Gain (loss) expected to be reclassified in one year or less	$ 1.5
Accumulated other comprehensive income (loss), cumulative changes in net gain (loss) from cash flow hedges, before tax	(20.7)	$ 35.0
Foreign currency
Derivatives, Fair Value [Line Items]
Gain (loss) expected to be reclassified in one year or less	1.4
Accumulated other comprehensive income (loss), cumulative changes in net gain (loss) from cash flow hedges, before tax	1.4	5.6
Foreign currency | Prepayments and other current assets
Derivatives, Fair Value [Line Items]
Derivative assets	4.6	7.2
Foreign currency | Accounts payable and accrued expenses
Derivatives, Fair Value [Line Items]
Derivative liabilities	8.6	1.1
Commodity contracts
Derivatives, Fair Value [Line Items]
Gain (loss) expected to be reclassified in one year or less	0.1
Accumulated other comprehensive income (loss), cumulative changes in net gain (loss) from cash flow hedges, before tax	0.1	(0.1)
Commodity contracts | Prepayments and other current assets
Derivatives, Fair Value [Line Items]
Derivative assets	0.1	0.1
Commodity contracts | Accounts payable and accrued expenses
Derivatives, Fair Value [Line Items]
Derivative liabilities	0.0	0.0
Net investment hedge
Derivatives, Fair Value [Line Items]
Gain (loss) expected to be reclassified in one year or less	0.0
Accumulated other comprehensive income (loss), cumulative changes in net gain (loss) from cash flow hedges, before tax	$ (22.2)	$ 29.5