Consolidated Statements of Changes in Equity (LLC) (MidAmerican Funding, LLC and Subsidiaries [Domain], USD $) In Millions, unless otherwise specified	MidAmerican Funding, LLC and Subsidiaries [Domain] USD ($)	MidAmerican Funding, LLC and Subsidiaries [Domain] Paid-in Capital [Member] USD ($)	MidAmerican Funding, LLC and Subsidiaries [Domain] Retained Earnings [Member] USD ($)	MidAmerican Funding, LLC and Subsidiaries [Domain] Accumulated Other Comprehensive Loss, Net [Member] USD ($)	MidAmerican Funding, LLC and Subsidiaries [Domain] Noncontrolling Interests [Member] USD ($)
Balance at Dec. 31, 2011	$ 4,000	$ 1,679	$ 2,327	$ (34)	$ 28
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	71		71		0
Other comprehensive income (loss)	(14)			(14)	0
Balance at Mar. 31, 2012	4,057	1,679	2,398	(48)	28
Balance at Dec. 31, 2012	4,351	1,679	2,669	(24)	27
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	100		100		0
Other comprehensive income (loss)	18			18	0
Balance at Mar. 31, 2013	$ 4,469	$ 1,679	$ 2,769	$ (6)	$ 27