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BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES (Transaction Gains (Losses) Resulting from Remeasurement) (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
Foreign Currency Transaction Gain (Loss), before Tax | $ 0.8 | $ 3.3 | $ (1.3)
Transaction Gains and Losses Resulting from Remeasurement [Member] |  |  |
Foreign Currency Transaction Gain (Loss), before Tax | (16.8) | 16.3 | 29.0
Cash and Cash Equivalents [Member] |  |  |
Foreign Currency Transaction Gain (Loss), before Tax | (1.0) | 1.5 | 10.6
Intercompany loan [Member] |  |  |
Foreign Currency Transaction Gain (Loss), before Tax | $ (16.6) | $ 11.5 | $ 19.7

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