Consolidated Statements of Comprehensive Income (MEC) (MidAmerican Energy Company and Subsidiaries [Member], USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
MidAmerican Energy Company and Subsidiaries [Member]
Net income	$ 355	$ 319	$ 357
Other comprehensive income (loss):
Unrealized gains on available-for-sale securities, net of tax of $2, $- and $2	3	1	2
Unrealized gains (losses) on cash flow hedges, net of tax of $4, $(3) and $11	7	(6)	18
Total other comprehensive income (loss), net of tax	10	(5)	20
Comprehensive income	$ 365	$ 314	$ 377