Summary of Significant Accounting Policies (MEC) Revenue Recognition (Details) (MidAmerican Energy Company and Subsidiaries [Member], USD $) In Millions, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
MidAmerican Energy Company and Subsidiaries [Member]
Notes to Consolidated Financial Statements [Line Items]
Unbilled revenue	$ 135	$ 141
Adjustment clauses and bill rider accounts receivable	$ 54	$ 24

The amount due for services rendered or products shipped, but not yet billed, recognized in conformity with revenue recognition criteria. This element is distinct from unbilled contracts receivables because this is based on noncontract transactions.

No definition available.

Name:	us-gaap_UnbilledReceivablesCurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant