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Fair Value Measurements - Schedule of Changes in Level 3 Liabilities (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2015 | Sep. 30, 2014 | Sep. 30, 2015 | Sep. 30, 2014
Contingent Payment Arrangements |  |  |  |  |
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |  |
Balance, beginning of period |  | $ 6.7 | $ 55.1 | $ 59.3 | $ 50.2
Net gains/losses | [1] | 0.4 | 1.9 | (41.2) | 6.8
Purchases and issuances |  | 0.0 | 0.0 | 6.5 | 0.0
Settlements and reductions |  | 0.0 | 0.0 | (17.5) | 0.0
Net transfers in and/or out of Level 3 |  | 0.0 | 0.0 | 0.0 | 0.0
Balance, end of period |  | 7.1 | 57.0 | 7.1 | 57.0
Net unrealized gains/losses relating to instruments still held at the reporting date | [1] | 0.4 | 1.9 | (41.2) | 6.8
Obligations to Related Parties |  |  |  |  |
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |  |
Balance, beginning of period |  | 127.3 | 98.4 | 93.1 | 76.9
Net gains/losses | [2] | 2.1 | 1.3 | 4.5 | 5.8
Purchases and issuances |  | 33.8 | 11.1 | 101.6 | 72.1
Settlements and reductions |  | (65.4) | (18.1) | (101.4) | (62.1)
Net transfers in and/or out of Level 3 |  | 0.0 | 0.0 | 0.0 | 0.0
Balance, end of period |  | 97.8 | 92.7 | 97.8 | 92.7
Net unrealized gains/losses relating to instruments still held at the reporting date | [2] | $ (0.3) | $ 0.2 | $ (4.4) | $ 2.2
[1] | Accretion and changes to the Company’s contingent payment arrangements are recorded in Imputed interest expense and contingent payment arrangements.
[2] | Gains and losses associated with agreements to repurchase Affiliate equity are recorded in Imputed interest expense and contingent payment arrangements. Gains and losses related to liabilities offsetting certain investments are recorded in Investment and other income.

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- Definition Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Liability Purchases And Issuances + References No definition available. + Details
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- Definition Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Liability Settlements And Reductions + References No definition available. + Details
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- Definition Amount of unrealized (holding) gain (loss) which is included in the statement of income (or changes in net assets) related to those liabilities still held at the reporting date for which fair value is measured on a recurring basis using significant unobservable inputs (Level 3). + 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 (d) -URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258 + Details
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. + References No definition available. + Details
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- Definition Amount of gain (loss) recognized on the income statement for financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. + 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 (c)(1) -URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258 + Details
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- Definition Amount of transfers of financial instrument classified as a liability into (out of) level 3 of the fair value hierarchy. + References No definition available. + Details
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- Definition Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. + 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 (c) -URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258 + Details
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