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FAIR VALUE MEASUREMENTS FAIR VALUE MEASUREMENTS (Fair Value Measurements, Nonrecurring) (Details) - USD ($) $ in Millions | 9 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2017 | Dec. 31, 2016
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Loans to and accounts receivable from the Canadian Entities | $ 51.9 | $ 48.6
Fair Value, Asset, Measured on a Nonrecurring Basis, Gain (Loss) Included in Earnings | 3.3 | (17.5)
Contingent Liabilities recognized in Consolidated Financials | 0.0 | 37.2
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Gain (Loss) Included in Earnings |  | 0.4
Fair Value, Inputs, Level 3 [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Loans to and accounts receivable from the Canadian Entities |  | $ 48.6
Contingent Liabilities recognized in Consolidated Financials | $ 0.0 |

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