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Fair Value Measurements - Schedule of Fair Value of Assets and Liabilities Measured on a Recurring Basis (Details) - USD ($) $ in Millions | Jun. 30, 2016 | Dec. 31, 2015
--- | --- | ---
Investments in marketable securities |  |  |
Trading securities |  | $ 96.0 | $ 19.4
Financial Liabilities |  |  |
Investments removed from fair value measurement on recurring basis |  | (169.6) | (198.3)
Fair Value Measured On A Recurring Basis |  |  |
Financial Assets |  |  |
Cash equivalents |  | 27.3 | 65.9
Investments in marketable securities |  |  |
Trading securities | [1] | 96.0 | 19.4
Available-for-sale securities | [1] | 107.6 | 180.5
Financial Liabilities |  |  |
Contingent payment arrangements | [2] | 8.0 | 10.2
Affiliate equity obligations | [3] | 27.0 | 62.3
Foreign currency forward contracts | [2] | 0.8 |
Investments removed from fair value measurement on recurring basis | [4] | (6.4) | (23.3)
Fair Value Measured On A Recurring Basis | Accounting Standards Update 2015-07 |  |  |
Financial Liabilities |  |  |
Investments removed from fair value measurement on recurring basis | [4] | 136.1 | 126.0
Obligations to related parties removed from fair value measurement on recurring basis | [4] | 73.2 | 75.0
Fair Value Measured On A Recurring Basis | Quoted Prices In Active Markets For Identical Assets (Level 1) |  |  |
Financial Assets |  |  |
Cash equivalents |  | 27.3 | 65.9
Investments in marketable securities |  |  |
Trading securities | [1] | 96.0 | 19.4
Available-for-sale securities | [1] | 107.6 | 180.5
Financial Liabilities |  |  |
Contingent payment arrangements | [2] | 0.0 | 0.0
Affiliate equity obligations | [3] | 0.0 | 0.0
Foreign currency forward contracts | [2] | 0.0 |
Investments removed from fair value measurement on recurring basis | [4] | (4.0) | (20.7)
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
Financial Liabilities |  |  |
Contingent payment arrangements | [2] | 0.0 | 0.0
Affiliate equity obligations | [3] | 0.0 | 0.0
Foreign currency forward contracts | [2] | 0.8 |
Investments removed from fair value measurement on recurring basis | [4] | (2.4) | (2.6)
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
Financial Liabilities |  |  |
Contingent payment arrangements | [2] | 8.0 | 10.2
Affiliate equity obligations | [3] | 27.0 | 62.3
Foreign currency forward contracts | [2] | 0.0 |
Investments removed from fair value measurement on recurring basis | [4] | $ 0.0 | $ 0.0
[1] | Principally investments in equity securities.
[2] | Amounts are presented within Other liabilities.
[3] | Amounts are presented within Other liabilities.(4) The Company adopted ASU 2015-07 and no longer includes $75.0 million and $73.2 million as of December 31, 2015 and June 30, 2016, respectively, of liabilities for which fair value was measured using NAV as a practical expedient. These liabilities were previously included in Obligations to related parties and upon removal, the remaining liabilities were re-labeled Affiliate equity obligations.
[4] | The Company adopted ASU 2015-07 and no longer includes $126.0 million and $136.1 million as of December 31, 2015 and June 30, 2016, respectively, of investments in certain entities for which fair value was measured using net asset value (“NAV”) as a practical expedient.

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- Definition Fair value of investments in certain entities that calculate net asset value per share, including, but not limited to, by unit, membership interest, or other ownership interest. Investments include, but are not limited to, investments in certain hedge funds, venture capital funds, private equity funds, real estate partnerships or funds. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 6A -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=36462937&loc=SL6742756-110258 + Details
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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 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 + Details
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