v2.4.0.6

Acquisitions, Divestitures and Discontinued Operations (Acquisition of Broad River and South Point Leases) (Details) (USD $) In Millions, unless otherwise specified	Dec. 08, 2010	Jul. 02, 2010
Broad River and South Point Leases [Line Items]
Broad River: debt extinguishment costs	$ 30
South Point: impairment loss	95
Total loss recorded for this transaction	125
Acquisition of Broad River and South Point Leases (Textuals) [Abstract]
Business Acquisition, Purchase Price Allocation, Notes Payable and Long-term Debt	297
Business Acquisition, Cost of Acquired Entity, Cash Paid	40
Business Acquisition, Purchase Price Allocation, Liabilities Assumed	85	97
Debt Eliminated In Acquisition	$ (212)

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