Employee Benefit Plans (MEC) (Details) (MidAmerican Energy Company [Member], USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
United States Defined Benefit Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 4	$ 4	$ 7	$ 9
Interest cost	9	8	18	16
Expected return on plan assets	(12)	(11)	(23)	(22)
Net amortization	0	2	1	5
Net periodic benefit cost (benefit)	1	3	3	8
United States Defined Benefit Other Postretirement Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	2	1	3	2
Interest cost	3	2	5	4
Expected return on plan assets	(4)	(4)	(7)	(7)
Net amortization	(1)	0	(2)	(1)
Net periodic benefit cost (benefit)	$ 0	$ (1)	$ (1)	$ (2)