Supplemental Cash Flows Information (MEC) (Details) (MidAmerican Energy Company [Member], USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
MidAmerican Energy Company [Member]
Interest paid, net of amounts capitalized	$ 144		$ 109		$ 123
Income taxes received, net	149		36		692
Cash Flow, Noncash Investing and Financing Activities Disclosure [Abstract]
Accounts payable related to utility plant additions	128		117		122
Deferred payments on equipment purchased for wind-powered generation	$ 0	[1]	$ 0	[1]	$ 406	[1]

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