Document and Entity Information Document	3 Months Ended
	Mar. 31, 2013	Apr. 30, 2013
Entity Information [Line Items]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Mar. 31, 2013
Document Fiscal Year Focus	2013
Document Fiscal Period Focus	Q1
Entity Filer Category	Non-accelerated Filer
Entity Registrant Name	MIDAMERICAN ENERGY COMPANY
Entity Central Index Key	0000928576
Current Fiscal Year End Date	--12-31
Entity Common Stock, Shares Outstanding		70,980,203
MidAmerican Funding, LLC and Subsidiaries [Domain]
Entity Information [Line Items]
Entity Filer Category	Non-accelerated Filer
Entity Registrant Name	MIDAMERICAN FUNDING, LLC
Entity Central Index Key	0001098296
Current Fiscal Year End Date	--12-31