Components of Accumulated Other Comprehensive Loss, Net (MEC) (Details) (MidAmerican Energy Company [Member], USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Other comprehensive income, unrealized gains on cash flow hedges	$ (14)	$ 7	$ 4	$ (7)
Other comprehensive income (loss)			4	(7)
Commodity Contract [Member] | Designated as Hedging Instrument [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Net losses reclassified to nonregulated cost of sales	1	14	6	27
Accumulated Other Comprehensive Loss, Net [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance, December 31, 2012, Unrealized Losses on Available-For-Fale Securities			(5)
Balance, December 31, 2012, Unrealized Losses on Cash Flow Hedges			(19)
Balance, December 31, 2012, Accumulated Other Comprehensive Loss, Net			(24)
Other comprehensive income, unrealized gains on available-for-sales securities			0
Other comprehensive income, unrealized gains on cash flow hedges			4
Other comprehensive income (loss)			4	(7)
Balance, June 30, 2013, Unrealized Losses on Available-For-Sale Securities	(5)		(5)
Balance, June 30, 2013, Unrealized Losses on Cash Flow Hedges	(15)		(15)
Balance, June 30, 2013, Accumulated Other Comprehensive Loss, Net	$ (20)		$ (20)