Income Taxes (MEC) (Tables) (MidAmerican Energy Company and Subsidiaries [Member])

12 Months Ended

Dec. 31, 2012

MidAmerican Energy Company and Subsidiaries [Member]

Income Tax Disclosure [Line Items]

Components of Income Tax Expense (Benefit) [Table Text Block]

MidAmerican Energy's income tax (benefit) expense consists of the following for the years ended December 31 (in millions):

	2012			2011			2010
Current:
Federal	$	(256	)	$	(474	)	$	(161	)
State	(21		)	(6		)	(25		)
	(277		)	(480		)	(186		)
Deferred:
Federal	200			453			125
State	(20		)	11			14
	180			464			139
Investment tax credits	(2		)	(1		)	(2		)
Total	$	(99	)	$	(17	)	$	(49	)

Effective Income Tax Rate Reconciliation [Table Text Block]

A reconciliation of the federal statutory income tax rate to the effective income tax rate applicable to income before income tax expense is as follows for the years ended December 31:

	2012		2011		2010
Federal statutory income tax rate	35	%	35	%	35	%
Income tax credits	(56	)	(32	)	(27	)
State income tax, net of federal income tax benefit	(10	)	1		(2	)
Income tax method changes	(6	)	(10	)	(17	)
Effects of ratemaking	—		—		(3	)
Other, net	(2	)	—		(2	)
Effective federal and state income tax rate	(39	)%	(6	)%	(16	)%

Components of Net Deferred Income Tax Liability [Table Text Block]

MidAmerican Energy's net deferred income tax liability consists of the following as of December 31 (in millions):

	2012			2011
Deferred income tax assets:
Regulatory liabilities	$	311		$	300
Employee benefits	83			96
Derivative contracts	32			48
Asset retirement obligations	132			122
Other	76			56
Total deferred income tax assets	634			622
Deferred income tax liabilities:
Depreciable property	(2,422		)	(2,183		)
Regulatory assets	(353		)	(333		)
Other	(26		)	(18		)
Total deferred income tax liabilities	(2,801		)	(2,534		)
Net deferred income tax liability	$	(2,167	)	$	(1,912	)
Reflected as:
Current assets - other	$	—		$	6
Current liabilities - other	(3		)	—
Deferred income taxes	(2,164		)	(1,918		)
	$	(2,167	)	$	(1,912	)

Net Unrecognized Tax Benefits Roll Forward [Table Text Block]

A reconciliation of the beginning and ending balances of MidAmerican Energy's net unrecognized tax benefits is as follows for the years ended December 31 (in millions):

	2012			2011
Beginning balance	$	46		$	79
Additions based on tax positions related to the current year	10			8
Additions for tax positions of prior years	25			4
Reductions based on tax positions related to the current year	(16		)	(2		)
Reductions for tax positions of prior years	(23		)	(41		)
Statute of limitations	(3		)	(1		)
Settlements	(2		)	—
Interest and penalties	(1		)	(1		)
Ending balance	$	36		$	46