Components of Accumulated Other Comprehensive Income (Loss), Net (MEC) (Details) (MidAmerican Energy Company [Member], USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Other comprehensive income, unrealized gains on available-for-sales securities	$ 1	$ 0
Other comprehensive income, unrealized gains on cash flow hedges	14	18
Other comprehensive income (loss)	15	18
Commodity Contract [Member] | Designated as Hedging Instrument [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Net gains (losses) reclassified to nonregulated cost of sales	(34)	5
Accumulated Other Comprehensive Income (Loss), Net [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance, December 31, 2013, Unrealized Losses on Available-For-Fale Securities	(4)
Balance, December 31, 2013, Unrealized Gains (Losses) on Cash Flow Hedges	(7)
Balance, December 31, 2013, Accumulated Other Comprehensive Income (Loss), Net	(11)
Other comprehensive income, unrealized gains on available-for-sales securities	1
Other comprehensive income, unrealized gains on cash flow hedges	14
Other comprehensive income (loss)	15	18
Balance, March 31, 2014, Unrealized Losses on Available-For-Sale Securities	(3)
Balance, March 31, 2014, Unrealized Gains (Losses) on Cash Flow Hedges	7
Balance, March 31, 2014, Accumulated Other Comprehensive Income (Loss), Net	$ 4