Segment Information Segment Information - MidAmerican Funding (Details) $ in Millions		3 Months Ended		6 Months Ended
		Jun. 30, 2017 USD ($)	Jun. 30, 2016 USD ($)	Jun. 30, 2017 USD ($) OperatingSegments ReportableSegments	Jun. 30, 2016 USD ($)	Dec. 31, 2016 USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments | OperatingSegments				8
Revenues		$ 4,554	$ 4,121	$ 8,720	$ 8,162
Operating income		1,049	854	2,020	1,807
Assets		87,809		$ 87,809		$ 85,440
MidAmerican Funding, LLC and Subsidiaries [Domain]
Segment Reporting Information [Line Items]
Number of reportable segments | ReportableSegments				2
Electric Domestic Regulated Revenue		537	481	$ 970	880
Revenues		659	585	1,355	1,211
Utilities Operating Expense, Depreciation and Amortization		141	110	258	220
Operating income		136	140	243	240
Assets	[1]	17,433		17,433		16,747
MidAmerican Funding, LLC and Subsidiaries [Domain] | Regulated Electric [Member]
Segment Reporting Information [Line Items]
Electric Domestic Regulated Revenue		537	481	970	880
Utilities Operating Expense, Depreciation and Amortization		130	100	237	199
Operating income		128	135	195	192
Assets	[1]	16,062		16,062		15,304
MidAmerican Funding, LLC and Subsidiaries [Domain] | Regulated Gas [Member]
Segment Reporting Information [Line Items]
Gas Domestic Regulated Revenue		120	102	382	328
Utilities Operating Expense, Depreciation and Amortization		11	10	21	21
Operating income		7	4	47	47
Assets	[1]	1,348		1,348		1,424
MidAmerican Funding, LLC and Subsidiaries [Domain] | Corporate and Other [Member]
Segment Reporting Information [Line Items]
Other Revenue, Net		2	2	3	3
Operating income		1	$ 1	1	$ 1
Assets	[1]	$ 23		$ 23		$ 19

[1] (1)Consists principally of cash and cash equivalents not included in either the regulated electric or regulated natural gas segments.