Segment Information Segment Information - MidAmerican Funding (Details) $ in Millions		3 Months Ended		6 Months Ended
		Jun. 30, 2019 USD ($)	Jun. 30, 2018 USD ($)	Jun. 30, 2019 USD ($) OperatingSegments ReportableSegments	Jun. 30, 2018 USD ($)	Dec. 31, 2018 USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments | OperatingSegments				8
Operating revenue		$ 4,894	$ 4,993	$ 9,504	$ 9,433
Operating income		959	972	1,878	1,843
Interest expense		(476)	(461)	(953)	(927)
Capitalized interest		17	15	33	27
Allowance for equity funds		38	24	70	45
Other, net		30	1	65	31
Income before income tax (benefit) expense and equity income		610	196	1,097	481
Assets		96,142		$ 96,142		$ 92,189
MidAmerican Funding, LLC and Subsidiaries [Domain]
Segment Reporting Information [Line Items]
Number of reportable segments | ReportableSegments				2
Operating revenue		660	718	$ 1,502	1,465
Operating income		94	87	210	166
Interest expense		(74)	(61)	(149)	(124)
Capitalized interest		7	4	13	8
Allowance for equity funds		17	13	32	23
Other, net		10	13	31	23
Income before income tax (benefit) expense and equity income		54	56	137	96
Assets	[1]	20,313		20,313		19,202
MidAmerican Funding, LLC and Subsidiaries [Domain] | Regulated electric
Segment Reporting Information [Line Items]
Operating revenue		538	589	1,080	1,058
Operating income		87	78	153	114
Assets	[1]	18,926		18,926		17,702
MidAmerican Funding, LLC and Subsidiaries [Domain] | Regulated natural gas
Segment Reporting Information [Line Items]
Operating revenue		111	127	406	402
Operating income		5	8	53	51
Assets	[1]	1,368		1,368		1,485
MidAmerican Funding, LLC and Subsidiaries [Domain] | Corporate and Other [Member]
Segment Reporting Information [Line Items]
Operating revenue		11	2	16	5
Operating income		2	$ 1	4	$ 1
Assets	[1]	$ 19		$ 19		$ 15

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