v3.8.0.1

Basis of Presentation and Summary of Significant Accounting Policies Property, Plant and Equipment, Net (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2017	Dec. 31, 2016
Property, Plant and Equipment [Line Items]
Buildings, machinery and equipment	$ 16,512	$ 16,468
Geothermal properties	1,480	1,377
Other	235	259
Property, plant and equipment, gross	18,227	18,104
Less: Accumulated depreciation	6,265	5,865
Property, plant and equipment, gross, less accumulated depreciation, depletion and amortization	11,962	12,239
Land	117	116
Construction in progress	754	658
Property, plant and equipment, net	$ 12,833	$ 13,013
Minimum [Member] | Building, Machinery and Equipment, Gross [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, estimated useful lives	3 years
Minimum [Member] | Geothermal Properties, Gross [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, estimated useful lives	13 years
Minimum [Member] | Property, Plant and Equipment, Other Types [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, estimated useful lives	3 years
Maximum [Member] | Building, Machinery and Equipment, Gross [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, estimated useful lives	46 years
Maximum [Member] | Geothermal Properties, Gross [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, estimated useful lives	58 years
Maximum [Member] | Property, Plant and Equipment, Other Types [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, estimated useful lives	46 years

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Amount of structure or a modification to a structure under construction. Includes recently completed structures or modifications to structures that have not been placed into service.

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