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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, 2016 | Dec. 31, 2015
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Finite-Lived Intangible Assets [Line Items] |  |
Definite lived intangible assets - Gross Carrying Amount | $ 78.4 | $ 78.4
Definite lived intangible assets - Accumulated Amortization | (24.6) | (20.2)
Definite lived intangible assets - Net Carrying Amount | 53.8 | 58.2
Below-market sales contracts, gross |  | (228.9)
Below-market sales contracts, accumulated amortization |  | 205.8
Below-market sales contracts, net |  | (23.1)
Other Current Liabilities [Member] |  |
Finite-Lived Intangible Assets [Line Items] |  |
Below-market sales contracts, gross |  | (23.1)
Below-market sales contracts, net | 0.0 | (23.1)
Other Liabilities [Member] |  |
Finite-Lived Intangible Assets [Line Items] |  |
Below-market sales contracts, gross |  | (205.8)
Below-market sales contracts, accumulated amortization |  | 205.8
Below-market sales contracts, net | 0.0 |
Permits [Member] | Other Assets [Member] |  |
Finite-Lived Intangible Assets [Line Items] |  |
Definite lived intangible assets - Gross Carrying Amount | 78.4 | 78.4
Definite lived intangible assets - Accumulated Amortization | (24.6) | (20.2)
Definite lived intangible assets - Net Carrying Amount | $ 53.8 | $ 58.2

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