v3.20.1

Basis of Presentation and Summary of Significant Accounting Policies - Property, Plant and Equipment, Net (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Dec. 31, 2019
Property, Plant and Equipment [Line Items]
Buildings, machinery and equipment	$ 16,560	$ 16,510
Geothermal properties	1,561	1,553
Other	287	291
Property, plant and equipment, gross	18,408	18,354
Less: Accumulated depreciation	6,955	6,851
Property, plant and equipment, gross, less accumulated depreciation, depletion and amortization	11,453	11,503
Land	128	128
Construction in progress	378	332
Property, plant and equipment, net	$ 11,959	$ 11,963
Minimum | Building, Machinery and Equipment, Gross
Property, Plant and Equipment [Line Items]
Property, plant and equipment, estimated useful lives	1 year 6 months
Minimum | Geothermal Properties, Gross
Property, Plant and Equipment [Line Items]
Property, plant and equipment, estimated useful lives	13 years
Minimum | Property, Plant and Equipment, Other Types
Property, Plant and Equipment [Line Items]
Property, plant and equipment, estimated useful lives	3 years
Maximum | Building, Machinery and Equipment, Gross
Property, Plant and Equipment [Line Items]
Property, plant and equipment, estimated useful lives	50 years
Maximum | Geothermal Properties, Gross
Property, Plant and Equipment [Line Items]
Property, plant and equipment, estimated useful lives	58 years
Maximum | Property, Plant and Equipment, Other Types
Property, Plant and Equipment [Line Items]
Property, plant and equipment, estimated useful lives	50 years

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Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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