Supplemental Cash Flows Information (MEC) (Details) (MidAmerican Energy Company and Subsidiaries [Member], USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012		Dec. 31, 2011		Dec. 31, 2010
MidAmerican Energy Company and Subsidiaries [Member]
Interest paid, net of amounts capitalized	$ 123		$ 156		$ 151
Income taxes received, net	692		221		124
Cash Flow, Noncash Investing and Financing Activities Disclosure [Abstract]
Accounts payable related to utility plant additions	122		102		29
Deferred payments on equipment purchased for wind-powered generation	$ 406	[1]	$ 647	[1]	$ 0	[1]

[1] In conjunction with the construction of wind-powered generating facilities, MidAmerican Energy accrued in gross utility plant in service amounts it is not contractually obligated to pay until a stated future date. Refer to Note 8 for additional information.