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Fair Value Measurements - Assets and Liabilities Measured on a Recurring Basis (Details) - Fair Value Measured On A Recurring Basis - USD ($) $ in Millions | Jun. 30, 2018 | Dec. 31, 2017
--- | --- | ---
Financial Assets |  |  |
Cash equivalents |  | $ 30.0 | $ 40.4
Investments | [1] | 84.1 | 77.8
Foreign currency forward contracts | [1] | 1.0 | 0.2
Financial Liabilities |  |  |
Contingent payment arrangements | [2] | 4.2 | 9.4
Affiliate equity obligations | [2] | 36.9 | 49.2
Foreign currency forward contracts | [2] | 1.1 | 0.6
Quoted Prices in Active Markets for Identical Assets (Level 1) |  |  |
Financial Assets |  |  |
Cash equivalents |  | 30.0 | 40.4
Investments | [1] | 84.1 | 77.8
Foreign currency forward contracts | [1] | 0.0 | 0.0
Financial Liabilities |  |  |
Contingent payment arrangements | [2] | 0.0 | 0.0
Affiliate equity obligations | [2] | 0.0 | 0.0
Foreign currency forward contracts | [2] | 0.0 | 0.0
Significant Other Observable Inputs (Level 2) |  |  |
Financial Assets |  |  |
Cash equivalents |  | 0.0 | 0.0
Investments | [1] | 0.0 | 0.0
Foreign currency forward contracts | [1] | 1.0 | 0.2
Financial Liabilities |  |  |
Contingent payment arrangements | [2] | 0.0 | 0.0
Affiliate equity obligations | [2] | 0.0 | 0.0
Foreign currency forward contracts | [2] | 1.1 | 0.6
Significant Unobservable Inputs (Level 3) |  |  |
Financial Assets |  |  |
Cash equivalents |  | 0.0 | 0.0
Investments | [1] | 0.0 | 0.0
Foreign currency forward contracts | [1] | 0.0 | 0.0
Financial Liabilities |  |  |
Contingent payment arrangements | [2] | 4.2 | 9.4
Affiliate equity obligations | [2] | 36.9 | 49.2
Foreign currency forward contracts | [2] | $ 0.0 | $ 0.0
[1] | Amounts are presented within Investments and other assets.
[2] | Amounts are presented within Other liabilities in the Consolidated Condensed Balance Sheets.

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- Definition 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. + References No definition available. + Details
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