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FAIR VALUE MEASUREMENTS (Fair Value, Assets and Liabilities Measured On Recurring Basis, Unobservable Input Reconciliation) (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2017 | Sep. 30, 2016 | Sep. 30, 2017 | Sep. 30, 2016
Fair Value Disclosures [Abstract] |  |  |  |
Document Fiscal Year Focus |  |  | 2017 |
Fair Value, Assets Measured On Recurring Basis, Unobservable Input Reconciliation [Roll Forward] |  |  |  |
Beginning balance | $ 72.5 | $ 25.8 | $ 31.6 | $ 7.8
Total gains (losses) |  |  |  |
Included in earnings | 60.6 | 14.6 | 156.0 | 62.6
Settlements | (43.6) | (12.0) | (98.1) | (42.0)
Ending balance - September 30 | 89.5 | 28.4 | 89.5 | 28.4
Total gains for the period included in earnings attributable to the change in unrealized gains on assets still held at the reporting date | 0.1 | 8.2 | 53.4 | 24.7
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward] |  |  |  |
Beginning balance | (20.9) | (2.6) | (0.5) | (3.4)
Total gains (losses) |  |  |  |
Included in earnings | (19.3) | (2.9) | (64.9) | (12.8)
Settlements | 30.9 | 2.8 | 56.1 | 13.5
Ending balance - September 30 | (9.3) | (2.7) | (9.3) | (2.7)
Total gains (losses) for the period included in earnings attributable to the change in unrealized losses on liabilities still held at the reporting date | $ 6.0 | $ (2.7) | $ (14.8) | $ (2.7)

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- Definition Fair Value, Liabilities Measured On Recurring Basis, Unobservable Input Reconciliation, Calculation [Abstract] + References No definition available. + Details
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- Definition This is focus fiscal year of the document report in CCYY format. For a 2006 annual report, which may also provide financial information from prior periods, fiscal 2006 should be given as the fiscal year focus. Example: 2006. + 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 assets 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=66048111&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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