v3.19.1

Basis of Presentation and Summary of Significant Accounting Policies Property, Plant and Equipment, Net (Details) - USD ($) $ in Millions | 3 Months Ended |
--- | --- | ---
Mar. 31, 2019 | Dec. 31, 2018
Property, Plant and Equipment [Line Items] |  |
Buildings, machinery and equipment | $ 16,538 | $ 16,400
Geothermal properties | 1,503 | 1,501
Other | 264 | 286
Property, plant and equipment, gross | 18,305 | 18,187
Less: Accumulated depreciation | 6,764 | 6,832
Property, plant and equipment, gross, less accumulated depreciation, depletion and amortization | 11,541 | 11,355
Land | 121 | 121
Construction in progress | 386 | 966
Property, plant and equipment, net | $ 12,048 | $ 12,442
Minimum [Member] | Building, Machinery and Equipment, Gross [Member] |  |
Property, Plant and Equipment [Line Items] |  |
Property, plant and equipment, estimated useful lives | 1 year 6 months |
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 | 50 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 | 50 years |

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