Segment Information Segment Information - MidAmerican Funding (Details) $ in Millions		3 Months Ended
		Mar. 31, 2020 USD ($) OperatingSegments ReportableSegments	Mar. 31, 2019 USD ($)	Dec. 31, 2019 USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments | OperatingSegments		8
Operating revenue		$ 4,527	$ 4,610
Operating income		919	919
Interest expense		(483)	(477)
Allowance for borrowed funds		17	16
Allowance for equity funds		34	32
Other, net		(27)	35
Income before income tax (benefit) expense and equity income		507	487
Assets		$ 100,806		$ 100,051
MidAmerican Funding, LLC and Subsidiaries [Domain]
Segment Reporting Information [Line Items]
Number of reportable segments | ReportableSegments		2
Operating revenue		$ 686	842
Operating income		102	116
Interest expense		(81)	(75)
Allowance for borrowed funds		3	6
Allowance for equity funds		8	15
Other, net		(6)	21
Income before income tax (benefit) expense and equity income		26	83
Assets	[1]	21,866		21,840
MidAmerican Funding, LLC and Subsidiaries [Domain] | Regulated electric
Segment Reporting Information [Line Items]
Operating revenue		471	542
Operating income		59	66
Assets	[1]	20,375		20,284
MidAmerican Funding, LLC and Subsidiaries [Domain] | Regulated natural gas
Segment Reporting Information [Line Items]
Operating revenue		209	295
Operating income		39	48
Assets	[1]	1,486		1,547
MidAmerican Funding, LLC and Subsidiaries [Domain] | Corporate and Other [Member]
Segment Reporting Information [Line Items]
Operating revenue		6	5
Operating income		4	$ 2
Assets	[1]	$ 5		$ 9

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