GOODWILL AND OTHER INTANGIBLE ASSETS AND LIABILITIES (Schedule Of Finite-Lived Intangible Assets By Major Class) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Finite-Lived Intangible Assets [Line Items]
Definite lived intangible assets - Gross Carrying Amount	$ 79.2	$ 184.5
Definite lived intangible assets - Accumulated Amortization	(16.5)	(89.1)
Definite lived intangible assets - Net Carrying Amount	62.7us-gaap_FiniteLivedIntangibleAssetsNet	95.4us-gaap_FiniteLivedIntangibleAssetsNet
Permits [Member] \| Other Assets [Member]
Finite-Lived Intangible Assets [Line Items]
Definite lived intangible assets - Gross Carrying Amount	79.2	127.4
Definite lived intangible assets - Accumulated Amortization	(16.5)	(35.9)
Definite lived intangible assets - Net Carrying Amount	62.7	91.5
Utility Contracts [Member] \| Other Assets [Member]
Finite-Lived Intangible Assets [Line Items]
Definite lived intangible assets - Gross Carrying Amount		54.7
Definite lived intangible assets - Accumulated Amortization		(53.1)
Definite lived intangible assets - Net Carrying Amount		1.6
Leases [Member] \| Other Assets [Member]
Finite-Lived Intangible Assets [Line Items]
Definite lived intangible assets - Gross Carrying Amount		2.4
Definite lived intangible assets - Accumulated Amortization		(0.1)
Definite lived intangible assets - Net Carrying Amount		2.3
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	182.8	159.7
Definite lived intangible assets - Net Carrying Amount	(46.1)	(69.2)
Below Market Sales Contracts [Member] \| Other Current Liabilities [Member]
Finite-Lived Intangible Assets [Line Items]
Definite lived intangible assets - Gross Carrying Amount	(23.0)	(23.0)
Definite lived intangible assets - Net Carrying Amount	(23.0)	(23.0)
Below Market Sales Contracts [Member] \| Other Liabilities [Member]
Finite-Lived Intangible Assets [Line Items]
Definite lived intangible assets - Gross Carrying Amount	(205.9)	(205.9)
Definite lived intangible assets - Accumulated Amortization	182.8	159.7
Definite lived intangible assets - Net Carrying Amount	$ (23.1)	$ (46.2)

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275

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