Employee Benefit Plans (MEC) Narrative (Details) (MidAmerican Energy Company [Member], USD $) In Millions, unless otherwise specified	9 Months Ended
Sep. 30, 2013
United States Pension Plans of US Entity, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Estimated employer contributions In current fiscal year	$ 8
Contributions by employer in current year	5
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Estimated employer contributions In current fiscal year	0
Contributions by employer in current year	$ 0

Amount of the employer's best estimate of contributions expected to be paid to the plan in the current fiscal period.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 6

-URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e2709-114920

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration