Risk Management and Hedging Activities (MEC) Not Designated as Hedging Contracts - Nonregulated (Details) (MidAmerican Energy Company [Member], Commodity Contract [Member], Not Designated as Hedging Instrument [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
Derivative Instruments, Gain (Loss) [Line Items]
Derivative Instruments, Gain (Loss) Recognized in Income, Net	$ 1	$ 0	$ 13	$ 1
Nonregulated operating revenue
Derivative Instruments, Gain (Loss) [Line Items]
Derivative Instruments, Gain (Loss) Recognized in Income, Net	1	3	(8)	1
Nonregulated cost of sales
Derivative Instruments, Gain (Loss) [Line Items]
Derivative Instruments, Gain (Loss) Recognized in Income, Net	$ 0	$ (3)	$ 21	$ 0