Employee Benefit Plans (MEC) Narrative (Details) (MidAmerican Energy Company and Subsidiaries [Member], USD $) In Millions, unless otherwise specified	6 Months Ended
	Jun. 30, 2012
United States Pension Plans of US Entity, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan Estimated Employer Contributions In Current Fiscal Year	$ 65
Defined Benefit Plan, Contributions by Employer	61
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan Estimated Employer Contributions In Current Fiscal Year	0
Defined Benefit Plan, Contributions by Employer	$ 0