Employee Benefit Plans (MEC) (Details) (MidAmerican Energy Company [Member], USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
United States Defined Benefit Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 3	$ 5
Interest cost	9	8
Expected return on plan assets	(11)	(11)
Net amortization	1	3
Net periodic benefit cost (benefit)	2	5
United States Defined Benefit Other Postretirement Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	1	1
Interest cost	2	2
Expected return on plan assets	(3)	(3)
Net amortization	(1)	(1)
Net periodic benefit cost (benefit)	$ (1)	$ (1)