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BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES (Adoption of New Accounting Standard) (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
COST OF GOODS SOLD AND OPERATING EXPENSES | $ (1,828.5) | $ (1,719.7) | $ (1,776.8)
Selling, general and administrative expenses | (105.8) | (117.8) | (110.0)
Miscellaneous - net | 27.7 | (30.7) | 24.8
OPERATING INCOME (LOSS) | 423.6 | 240.8 | 151.3
Other non-operating income (expense) | 3.2 | 0.4 | (2.6)
Net income (loss) | 363.1 | $ 199.3 | $ (748.4)
Estimated Adjustment [Member] |  |  |
COST OF GOODS SOLD AND OPERATING EXPENSES | 2.4 |  |
Selling, general and administrative expenses | (7.7) |  |
Miscellaneous - net | (1.7) |  |
OPERATING INCOME (LOSS) | (7.0) |  |
Other non-operating income (expense) | 7.0 |  |
Net income (loss) | 0.0 |  |
Estimated post adjustment [Member] |  |  |
COST OF GOODS SOLD AND OPERATING EXPENSES | (1,826.1) |  |
Selling, general and administrative expenses | (113.5) |  |
Miscellaneous - net | 26.0 |  |
OPERATING INCOME (LOSS) | 416.6 |  |
Other non-operating income (expense) | 10.2 |  |
Net income (loss) | $ 363.1 |  |

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