Acquisitions, Divestitures and Discontinued Operations (Acquisition of Broad River and South Point Leases) (Details) (USD $) In Millions, unless otherwise specified	Dec. 08, 2010
Business Acquisition [Line Items]
Debt Extinguishment Costs Due To Acquisition	$ 30
Impairment Loss Due To Acquisition	95
Business Acquisition, Preexisting Relationship, Gain (Loss) Recognized	$ 125

Income (expense) and gain (loss) recognized from the settlement of a preexisting relationship between the acquirer and the acquiree.

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