Segment Information Segment Information - MidAmerican Funding (Details) $ in Millions		3 Months Ended		9 Months Ended
		Sep. 30, 2020 USD ($)	Sep. 30, 2019 USD ($)	Sep. 30, 2020 USD ($) OperatingSegments ReportableSegments	Sep. 30, 2019 USD ($)	Dec. 31, 2019 USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments | OperatingSegments				8
Operating revenue		$ 6,193	$ 5,644	$ 15,332	$ 15,148
Operating income		1,547	1,450	3,402	3,328
Interest expense		(504)	(475)	(1,490)	(1,428)
Allowance for borrowed funds		24	23	60	56
Allowance for equity funds		50	56	122	126
Other, net		36	2	61	67
Income before income tax (benefit) expense and equity income		2,967	847	4,619	1,944
Assets		109,186		$ 109,186		$ 100,051
MidAmerican Funding, LLC and Subsidiaries [Domain]
Segment Reporting Information [Line Items]
Number of reportable segments | ReportableSegments				2
Operating revenue		812	797	$ 2,114	2,299
Operating income		232	234	444	444
Interest expense		(79)	(74)	(238)	(223)
Allowance for borrowed funds		5	7	12	20
Allowance for equity funds		16	27	33	59
Other, net		15	5	30	36
Income before income tax (benefit) expense and equity income		189	199	281	336
Assets	[1]	22,548		22,548		21,840
MidAmerican Funding, LLC and Subsidiaries [Domain] | Regulated electric
Segment Reporting Information [Line Items]
Operating revenue		728	712	1,717	1,792
Operating income		238	243	398	396
Assets	[1]	20,973		20,973		20,284
MidAmerican Funding, LLC and Subsidiaries [Domain] | Regulated natural gas
Segment Reporting Information [Line Items]
Operating revenue		80	76	384	482
Operating income		(6)	(8)	40	45
Assets	[1]	1,558		1,558		1,547
MidAmerican Funding, LLC and Subsidiaries [Domain] | Corporate and Other [Member]
Segment Reporting Information [Line Items]
Operating revenue		4	9	13	25
Operating income		0	$ (1)	6	$ 3
Assets	[1]	$ 17		$ 17		$ 9

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