Segment Information (LLC) (Details) (MidAmerican Funding, LLC and Subsidiaries [Domain], USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2014 ReportableSegments		Mar. 31, 2013	Dec. 31, 2013
Segment Reporting Information [Line Items]
Number of Reportable Segments	3
Regulated electric	$ 450		$ 415
Regulated gas	511		315
Nonregulated	269		191
Total operating revenue	1,230		921
Depreciation and amortization	85		107
Total operating income	153		106
Assets	13,303	[1]		13,167	[1]
Regulated electric [Member]
Segment Reporting Information [Line Items]
Regulated electric	450		415
Depreciation and amortization	75		98
Total operating income	83		50
Assets	11,813	[1]		11,723	[1]
Regulated gas [Member]
Segment Reporting Information [Line Items]
Regulated gas	511		315
Depreciation and amortization	10		9
Total operating income	58		45
Assets	1,305	[1]		1,285	[1]
Nonregulated energy [Member]
Segment Reporting Information [Line Items]
Nonregulated	264		190
Total operating income	12		11
Assets	164	[1]		131	[1]
Other [Member]
Segment Reporting Information [Line Items]
Nonregulated	5		1
Assets	$ 21	[1]		$ 28	[1]

[1] (1)Total assets by reportable segment reflect the assignment of goodwill to applicable reporting units.