v2.4.0.8

Basis of Presentation and Summary of Significant Accounting Policies Property, Plant and Equipment, Net (Details) (USD $) In Millions, unless otherwise specified	Sep. 30, 2013		Dec. 31, 2012
Property, Plant and Equipment [Line Items]
Buildings, machinery and equipment	$ 15,862	[1]	$ 14,774	[1]
Geothermal properties	1,256		1,243
Other	155		142
Property, Plant and Equipment, Gross	17,273		16,159
Less: Accumulated depreciation	4,768		4,390
Property, Plant and Equipment, Gross, Less Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment	12,505		11,769
Land	103		98
Construction in progress	431		1,138
Property, plant and equipment, net	$ 13,039		$ 13,005
[1] The change from December 31, 2012 to September 30, 2013 can primarily be attributed to our Russell City and Los Esteros power plants commencing commercial operations during the third quarter of 2013.

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