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Fair Value Measurements - Schedule of Fair Value of Assets and Liabilities Measured on a Recurring Basis (Details) - USD ($) $ in Millions | Sep. 30, 2015 | Dec. 31, 2014
--- | --- | ---
Investments in marketable securities |  |  |  |
Trading securities |  | $ 22.2 |  | $ 22.3
Other investments |  | 209.3 |  | 210.0
Fair Value Measured On A Recurring Basis |  |  |  |
Financial Assets |  |  |  |
Cash equivalents |  | 49.0 |  | 59.1
Investments in marketable securities |  |  |  |
Trading securities | [1] | 22.2 |  | 22.3
Available-for-sale securities | [1] | 149.6 |  | 150.3
Other investments |  | 158.3 |  | 167.2
Foreign currency forward contracts | [2] | 0.8 |  |
Financial Liabilities |  |  |  |
Contingent payment arrangements | [3] | 7.1 |  | 59.3
Obligations to related parties | [3] | 97.8 |  | 93.1
Interest rate derivatives |  | 0.7 | [3] | 1.4
Foreign currency forward contracts | [2] | 0.2 |  | 0.5
Fair Value Measured On A Recurring Basis | Quoted Prices In Active Markets For Identical Assets (Level 1) |  |  |  |
Financial Assets |  |  |  |
Cash equivalents |  | 49.0 |  | 59.1
Investments in marketable securities |  |  |  |
Trading securities | [1] | 22.2 |  | 22.3
Available-for-sale securities | [1] | 149.6 |  | 150.3
Other investments |  | 20.2 |  | 13.6
Foreign currency forward contracts | [2] | 0.0 |  |
Financial Liabilities |  |  |  |
Contingent payment arrangements | [3] | 0.0 |  | 0.0
Obligations to related parties | [3] | 0.0 |  | 0.0
Interest rate derivatives |  | 0.0 | [3] | 0.0
Foreign currency forward contracts | [2] | 0.0 |  | 0.0
Fair Value Measured On A Recurring Basis | Significant Other Observable Inputs (Level 2) |  |  |  |
Financial Assets |  |  |  |
Cash equivalents |  | 0.0 |  | 0.0
Investments in marketable securities |  |  |  |
Trading securities | [1] | 0.0 |  | 0.0
Available-for-sale securities | [1] | 0.0 |  | 0.0
Other investments |  | 5.7 |  | 19.4
Foreign currency forward contracts | [2] | 0.8 |  |
Financial Liabilities |  |  |  |
Contingent payment arrangements | [3] | 0.0 |  | 0.0
Obligations to related parties | [3] | 0.0 |  | 0.0
Interest rate derivatives |  | 0.7 | [3] | 1.4
Foreign currency forward contracts | [2] | 0.2 |  | 0.5
Fair Value Measured On A Recurring Basis | Significant Other Unobservable Inputs (Level 3) |  |  |  |
Financial Assets |  |  |  |
Cash equivalents |  | 0.0 |  | 0.0
Investments in marketable securities |  |  |  |
Trading securities | [1] | 0.0 |  | 0.0
Available-for-sale securities | [1] | 0.0 |  | 0.0
Other investments |  | 132.4 |  | 134.2
Foreign currency forward contracts | [2] | 0.0 |  |
Financial Liabilities |  |  |  |
Contingent payment arrangements | [3] | 7.1 |  | 59.3
Obligations to related parties | [3] | 97.8 |  | 93.1
Interest rate derivatives |  | 0.0 | [3] | 0.0
Foreign currency forward contracts | [2] | $ 0.0 |  | $ 0.0
[1] | Principally investments in equity securities.
[2] | Amounts are presented within Other assets or Other liabilities in the accompanying Consolidated Balance Sheets.
[3] | Amounts are presented within Other liabilities in the accompanying Consolidated Balance Sheets.

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