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GOODWILL AND OTHER INTANGIBLE ASSETS AND LIABILITIES (Schedule Of Finite-Lived Intangible Assets By Major Class) (Details) - USD ($) $ in Millions | Dec. 31, 2015 | Dec. 31, 2014
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Finite-Lived Intangible Assets [Line Items] |  |
Definite lived intangible assets - Gross Carrying Amount | $ 78.4 | $ 79.2
Definite lived intangible assets - Accumulated Amortization | (20.2) | (16.5)
Definite lived intangible assets - Net Carrying Amount | 58.2 | 62.7
Permits [Member] | Other Assets [Member] |  |
Finite-Lived Intangible Assets [Line Items] |  |
Definite lived intangible assets - Gross Carrying Amount | 78.4 | 79.2
Definite lived intangible assets - Accumulated Amortization | (20.2) | (16.5)
Definite lived intangible assets - Net Carrying Amount | 58.2 | 62.7
Below Market Sales Contracts [Member] |  |
Finite-Lived Intangible Assets [Line Items] |  |
Definite lived intangible assets - Gross Carrying Amount | (228.9) | (228.9)
Definite lived intangible assets - Accumulated Amortization | 205.8 | 182.8
Definite lived intangible assets - Net Carrying Amount | (23.1) | (46.1)
Below Market Sales Contracts [Member] | Other Current Liabilities [Member] |  |
Finite-Lived Intangible Assets [Line Items] |  |
Definite lived intangible assets - Gross Carrying Amount | (23.1) | (23.0)
Definite lived intangible assets - Net Carrying Amount | (23.1) | (23.0)
Below Market Sales Contracts [Member] | Other Liabilities [Member] |  |
Finite-Lived Intangible Assets [Line Items] |  |
Definite lived intangible assets - Gross Carrying Amount | (205.8) | (205.9)
Definite lived intangible assets - Accumulated Amortization | 205.8 | 182.8
Definite lived intangible assets - Net Carrying Amount | $ 0.0 | $ (23.1)

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