Fair Value Measurements (Details) - Recurring basis - USD ($) $ in Millions	Jun. 30, 2017	Dec. 31, 2016
Fair value of assets and liabilities measured on recurring basis
Short-term investments	$ 43.2	$ 138.6
Forward contracts		8.4
Forward contracts	(11.5)
Total	31.7	147.0
Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair value of assets and liabilities measured on recurring basis
Short-term investments	43.2	138.6
Total	43.2	138.6
Significant Observable Inputs (Level 2)
Fair value of assets and liabilities measured on recurring basis
Forward contracts		8.4
Forward contracts	(11.5)
Total	$ (11.5)	$ 8.4

Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Cash
-URI http://asc.fasb.org/extlink&oid=6506951

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Cash Equivalents
-URI http://asc.fasb.org/extlink&oid=6507016

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Fair value of asset after deduction of liability.

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