Other, Net - MidAmerican Funding (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Component of Other Income (Expense), Nonoperating [Line Items]
Other Nonrecurring (Income) Expense	$ 455	$ 62	$ (8)
Other, net	(398)	36	39
MidAmerican Funding, LLC and Subsidiaries [Domain]
Component of Other Income (Expense), Nonoperating [Line Items]
Other Nonrecurring (Income) Expense	29	0	0
Other, net	(9)	19	19
MidAmerican Funding, LLC and Subsidiaries [Domain] | Corporate Owned Life Insurance Income (Loss) [Member]
Component of Other Income (Expense), Nonoperating [Line Items]
Other, net	13	8	4
MidAmerican Funding, LLC and Subsidiaries [Domain] | Available-For-Sale Securities, Gross Gain (Loss) [Member]
Component of Other Income (Expense), Nonoperating [Line Items]
Other, net	0	5	0
MidAmerican Funding, LLC and Subsidiaries [Domain] | Gains (Losses) on Disposition of Assets [Member]
Component of Other Income (Expense), Nonoperating [Line Items]
Other Nonrecurring (Income) Expense			13
Other, net	1	3	13
MidAmerican Funding, LLC and Subsidiaries [Domain] | Gain (Loss) on Extinguishment of Debt [Member]
Component of Other Income (Expense), Nonoperating [Line Items]
Other, net	(29)	0	0
MidAmerican Funding, LLC and Subsidiaries [Domain] | Other Income (Expense) [Member]
Component of Other Income (Expense), Nonoperating [Line Items]
Other, net	$ 6	$ 3	$ 2