Property, Plant and Equipment, Net (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2017	Dec. 31, 2016
Property, Plant and Equipment [Line Items]
Property, plant and equipment in service, net	$ 60,538	$ 60,411
Construction in Progress, Gross	2,350	2,098
Property, plant and equipment, net	62,888	62,509
Regulated assets [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment	78,252	78,478
Accumulated depreciation and amortization	(23,515)	(23,603)
Property, plant and equipment in service, net	54,737	54,875
Construction in Progress, Gross	2,100	1,800
Regulated assets [Member] | Utility generation, transmission and distribution systems
Property, Plant and Equipment [Line Items]
Property, plant and equipment	$ 71,308	71,536
Regulated assets [Member] | Utility generation, transmission and distribution systems | Minimum [Member]
Property, Plant and Equipment [Line Items]
Depreciable Life	5 years
Regulated assets [Member] | Utility generation, transmission and distribution systems | Maximum [Member]
Property, Plant and Equipment [Line Items]
Depreciable Life	80 years
Regulated assets [Member] | Interstate natural gas pipeline assets
Property, Plant and Equipment [Line Items]
Property, plant and equipment	$ 6,944	6,942
Regulated assets [Member] | Interstate natural gas pipeline assets | Minimum [Member]
Property, Plant and Equipment [Line Items]
Depreciable Life	3 years
Regulated assets [Member] | Interstate natural gas pipeline assets | Maximum [Member]
Property, Plant and Equipment [Line Items]
Depreciable Life	80 years
Unregulated operation [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment	$ 6,937	6,596
Accumulated depreciation and amortization	(1,136)	(1,060)
Property, plant and equipment in service, net	5,801	5,536
Unregulated operation [Member] | Independent power plants
Property, Plant and Equipment [Line Items]
Property, plant and equipment	$ 5,856	5,594
Unregulated operation [Member] | Independent power plants | Minimum [Member]
Property, Plant and Equipment [Line Items]
Depreciable Life	5 years
Unregulated operation [Member] | Independent power plants | Maximum [Member]
Property, Plant and Equipment [Line Items]
Depreciable Life	30 years
Unregulated operation [Member] | Other assets
Property, Plant and Equipment [Line Items]
Property, plant and equipment	$ 1,081	$ 1,002
Unregulated operation [Member] | Other assets | Minimum [Member]
Property, Plant and Equipment [Line Items]
Depreciable Life	3 years
Unregulated operation [Member] | Other assets | Maximum [Member]
Property, Plant and Equipment [Line Items]
Depreciable Life	30 years
Electricity Generation Plant, Non-Nuclear [Member] | MidAmerican Energy Company and Subsidiaries [Member] | Regulated assets [Member]
Property, Plant and Equipment [Line Items]
Change in Accounting Estimates, Impact on Future Periods	$ 34
Change in Accounting Estimates, Impact on Current Period From Prior Year Change	$ 9