Consolidated Statements of Changes in Equity (LLC) (MidAmerican Funding, LLC and Subsidiaries [Domain], USD $) In Millions	MidAmerican Funding, LLC and Subsidiaries [Domain] USD ($)	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, 2009	$ 3,459	$ 1,679	$ 1,798	$ (49)	$ 31
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	234		234		0
Other comprehensive income (loss)	(3)			(3)	0
Repurchase of preferred securities of subsidiary	(2)				(2)
Distributions to member	(114)		(114)
Distributions to noncontrolling interests	(1)				(1)
Balance at Sep. 30, 2010	3,573	1,679	1,918	(52)	28
Balance at Jun. 30, 2010
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	103
Other comprehensive income (loss)	(9)
Balance at Sep. 30, 2010	3,573	1,679
Balance at Dec. 31, 2010	3,701	1,679	2,023	(29)	28
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	218		217		1
Other comprehensive income (loss)	17			17	0
Distributions to member	0
Distributions to noncontrolling interests	(1)				(1)
Balance at Sep. 30, 2011	3,935	1,679	2,240	(12)	28
Balance at Jun. 30, 2011
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	104
Other comprehensive income (loss)	4
Balance at Sep. 30, 2011	$ 3,935	$ 1,679