Segment Information Segment Information - MidAmerican Funding (Details) $ in Millions		3 Months Ended
		Mar. 31, 2017 USD ($) OperatingSegments ReportableSegments	Mar. 31, 2016 USD ($)	Dec. 31, 2016 USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments | OperatingSegments		8
Revenues		$ 4,166	$ 4,041
Operating income		971	953
Assets		$ 86,525		$ 85,440
MidAmerican Funding, LLC and Subsidiaries [Domain]
Segment Reporting Information [Line Items]
Number of reportable segments | ReportableSegments		2
Electric Domestic Regulated Revenue		$ 433	399
Revenues		696	626
Utilities Operating Expense, Depreciation and Amortization		117	110
Operating income		107	100
Assets	[1]	17,261		16,747
MidAmerican Funding, LLC and Subsidiaries [Domain] | Regulated Electric [Member]
Segment Reporting Information [Line Items]
Electric Domestic Regulated Revenue		433	399
Utilities Operating Expense, Depreciation and Amortization		107	99
Operating income		67	57
Assets	[1]	15,850		15,304
MidAmerican Funding, LLC and Subsidiaries [Domain] | Regulated Gas [Member]
Segment Reporting Information [Line Items]
Gas Domestic Regulated Revenue		262	226
Utilities Operating Expense, Depreciation and Amortization		10	11
Operating income		40	43
Assets	[1]	1,392		1,424
MidAmerican Funding, LLC and Subsidiaries [Domain] | Corporate and Other [Member]
Segment Reporting Information [Line Items]
Other Revenue, Net		1	$ 1
Assets	[1]	$ 19		$ 19

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