Segment Information (LLC) (Details) (MidAmerican Funding, LLC and Subsidiaries [Domain], USD $) In Millions, unless otherwise specified	3 Months Ended			6 Months Ended
	Jun. 30, 2014		Jun. 30, 2013	Jun. 30, 2014 ReportableSegments		Jun. 30, 2013	Dec. 31, 2013
Segment Reporting Information [Line Items]
Number of Reportable Segments				3
Regulated electric	$ 426		$ 411	$ 876		$ 826
Regulated gas	136		142	647		457
Nonregulated	213		206	482		397
Total operating revenue	775		759	2,005		1,680
Depreciation and amortization	85		104	170		211
Total operating income	51		43	204		149
Assets	13,980	[1]		13,980	[1]		13,167	[1]
Regulated electric [Member]
Segment Reporting Information [Line Items]
Regulated electric	426		411	876		826
Depreciation and amortization	76		95	151		193
Total operating income	48		31	131		81
Assets	12,583	[1]		12,583	[1]		11,723	[1]
Regulated gas [Member]
Segment Reporting Information [Line Items]
Regulated gas	136		142	647		457
Depreciation and amortization	9		9	19		18
Total operating income	(3)		4	55		49
Assets	1,212	[1]		1,212	[1]		1,285	[1]
Nonregulated energy [Member]
Segment Reporting Information [Line Items]
Nonregulated	207		204	471		394
Total operating income	6		8	18		19
Assets	162	[1]		162	[1]		131	[1]
Other [Member]
Segment Reporting Information [Line Items]
Nonregulated	6		2	11		3
Assets	$ 23	[1]		$ 23	[1]		$ 28	[1]

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