Fair Value Measurements and Risk - Derivative Instruments (Details) - USD ($) $ in Millions	Sep. 30, 2017	Dec. 31, 2016
Asset Derivatives
Total derivatives	$ 3.3	$ 8.8
Liability Derivatives
Total derivatives	22.1	6.9
Designated as Hedging Instrument \| Other current assets
Asset Derivatives
Currency contracts	2.9	4.0
Interest rate contracts	0.0	0.0
Designated as Hedging Instrument \| Other assets
Asset Derivatives
Currency contracts	0.0	4.0
Interest rate contracts	0.0	0.0
Designated as Hedging Instrument \| Other current liabilities
Liability Derivatives
Currency contracts	0.0	0.0
Interest rate derivatives	1.7	2.8
Designated as Hedging Instrument \| Other liabilities
Liability Derivatives
Currency contracts	17.6	0.0
Interest rate derivatives	2.5	3.2
Not Designated as Hedging Instrument \| Other current assets
Asset Derivatives
Currency contracts	0.4	0.8
Not Designated as Hedging Instrument \| Other current liabilities
Liability Derivatives
Currency contracts	$ 0.3	$ 0.9

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+ References

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-Publisher FASB
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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Fair value portion of asset contracts related to the exchange of different currencies, including, but not limited to, foreign currency options, forward contracts, and swaps.

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Fair value as of the balance sheet date of all interest rate derivative liabilities designated as cash flow hedging instruments.

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