Employee Benefit Plans (MEC) (Tables) (MidAmerican Energy Company and Subsidiaries [Member])

12 Months Ended

Dec. 31, 2012

MidAmerican Energy Company and Subsidiaries [Member]

Defined Benefit Plan Disclosure [Line Items]

Schedule of Net Benefit Costs [Table Text Block]

Net periodic benefit cost for the plans of MidAmerican Energy and the aforementioned affiliates included the following components for the years ended December 31 (in millions):



	Pension									Other Postretirement
	2012			2011			2010			2012			2011			2010

Service cost	$	18		$	18		$	17		$	4		$	4		$	4
Interest cost	37			39			39			8			10			11
Expected return on plan assets	(45		)	(43		)	(40		)	(13		)	(13		)	(13		)
Net amortization	4			—			—			(3		)	(2		)	(2		)
Net periodic benefit cost (benefit)	$	14		$	14		$	16		$	(4	)	$	(1	)	$	—

Schedule of Changes in Fair Value of Plan Assets [Table Text Block]

The following table is a reconciliation of the fair value of plan assets for the years ended December 31 (in millions):



	Pension						Other Postretirement
	2012			2011			2012			2011

Plan assets at fair value, beginning of year	$	555		$	546		$	213		$	216
Employer contributions	65			55			1			2
Participant contributions	—			—			2			7
Actual return on plan assets	74			—			25			4
Benefits paid	(51		)	(46		)	(15		)	(16		)
Plan assets at fair value, end of year	$	643		$	555		$	226		$	213

Schedule of Changes in Projected Benefit Obligations [Table Text Block]

The following table is a reconciliation of the benefit obligations for the years ended December 31 (in millions):



	Pension						Other Postretirement
	2012			2011			2012			2011

Benefit obligation, beginning of year	$	799		$	738		$	198		$	189
Service cost	18			18			4			4
Interest cost	37			39			8			10
Participant contributions	—			—			2			7
Plan amendments	—			—			—			(18		)
Actuarial loss (gain)	43			50			16			22
Benefits paid	(51		)	(46		)	(15		)	(16		)
Benefit obligation, end of year	$	846		$	799		$	213		$	198
Accumulated benefit obligation, end of year	$	821		$	771

Schedule of Benefit Obligations in Excess of Fair Value of Plan Assets [Table Text Block]

The funded status of the plans and the amounts recognized on the Consolidated Balance Sheets as of December 31 are as follows (in millions):



	Pension						Other Postretirement
	2012			2011			2012		2011

Plan assets at fair value, end of year	$	643		$	555		$	226	$	213
Less - Benefit obligation, end of year	846			799			213		198
Funded status	$	(203	)	$	(244	)	$	13	$	15

Amounts recognized on the Consolidated Balance Sheets:
Other assets	$	—		$	—		$	13	$	15
Other current liabilities	(8		)	(8		)	—		—
Other liabilities	(195		)	(236		)	—		—
Amounts recognized	$	(203	)	$	(244	)	$	13	$	15

Schedule of Net Periodic Benefit Costs Not Yet Recognized [Table Text Block]

The portion of the funded status of the plans not yet recognized in net periodic benefit cost as of December 31 is as follows (in millions):



	Pension				Other Postretirement
	2012		2011		2012			2011

Net loss	$	121	$	111	$	51		$	48
Prior service cost (credit)	4		4		(53		)	(58		)
Total	$	125	$	115	$	(2	)	$	(10	)

A reconciliation of the amounts not yet recognized as components of net periodic benefit cost for the years ended December 31, 2012 and 2011 is as follows (in millions):



	Regulatory Asset			Regulatory Liability			Receivables (Payables) with Affiliates			Total
Pension
Balance, December 31, 2010	$	14		$	(1	)	$	9		$	22
Net gain arising during the year	85			1			7			93
Balance, December 31, 2011	99			—			16			115
Net loss arising during the year	14			—			—			14
Net amortization	(3		)	—			(1		)	(4		)
Total	11			—			(1		)	10
Balance, December 31, 2012	$	110		$	—		$	15		$	125



	Regulatory Asset			Regulatory Liability			Receivables (Payables) with Affiliates			Total
Other Postretirement
Balance, December 31, 2010	$	—		$	(8	)	$	(14	)	$	(22	)
Net loss arising during the year	16			8			5			29
Prior service credit arising during the year	(15		)	—			(4		)	(19		)
Net amortization	1			—			1			2
Total	2			8			2			12
Balance, December 31, 2011	2			—			(12		)	(10		)
Net loss (gain) arising during the year	6			—			(2		)	4
Net amortization	3			—			1			4
Total	9			—			(1		)	8
Balance, December 31, 2012	$	11		$	—		$	(13	)	$	(2	)

Schedule of Defined Benefit Plan, Amounts To Be Recognized In Following Year [Table Text Block]

The net loss and prior service cost (credit) that will be amortized in 2013 into net periodic benefit cost are estimated to be as follows (in millions):



	Net Loss		Prior Service Cost (Credit)			Total

Pension	$	10	$	1		$	11
Other postretirement	3		(6		)	(3		)
Total	$	13	$	(5	)	$	8

Schedule of Assumptions Used [Table Text Block]

Assumptions used to determine benefit obligations and net periodic benefit cost were as follows:



	Pension						Other Postretirement
	2012		2011		2010		2012		2011		2010
Benefit obligations as of December 31:
Discount rate	4.00	%	4.75	%	5.50	%	3.75	%	4.75	%	5.50	%
Rate of compensation increase	3.00	%	3.50	%	3.50	%	N/A		N/A		N/A

Net periodic benefit cost for the years ended December 31:
Discount rate	4.75	%	5.50	%	6.00	%	4.75	%	5.50	%	6.00	%
Expected return on plan assets⁽¹⁾	7.50	%	7.50	%	7.50	%	7.50	%	7.50	%	7.50	%
Rate of compensation increase	3.50	%	3.50	%	3.00	%	N/A		N/A		N/A


(1)	Amounts reflected are pre-tax values. Assumed after-tax returns for a taxable, non-union other postretirement plan were 5.75% for 2012, 2011 and 2010.



	2012		2011
Assumed healthcare cost trend rates as of December 31:
Healthcare cost trend rate assumed for next year	8.00	%	7.40	%
Rate that the cost trend rate gradually declines to	5.00	%	5.00	%
Year that the rate reaches the rate it is assumed to remain at	2018		2016

Schedule of Effect of One-Percentage-Point Change in Assumed Health Care Cost Trend Rates [Table Text Block]

A one percentage-point change in assumed healthcare cost trend rates would have the following effects (in millions):



	One Percentage-Point
	Increase		Decrease
Increase (decrease) in:
Total service and interest cost	$	—	$	—
Other postretirement benefit obligation	1		(1		)

Schedule of Expected Benefit Payments [Table Text Block]

Net periodic benefit costs assigned to MidAmerican Energy affiliates are reimbursed currently in accordance with its intercompany administrative services agreement. The expected benefit payments to participants in MidAmerican Energy's pension and other postretirement benefit plans for 2013 through 2017 and for the five years thereafter are summarized below (in millions):



	Projected Benefit Payments
	Pension		Other Postretirement

2013	$	53	$	15
2014	56		15
2015	56		16
2016	58		17
2017	61		18
2018-22	310		92

Schedule of Allocation of Plan Assets [Table Text Block]

The target allocations (percentage of plan assets) for MidAmerican Energy's pension and other postretirement benefit plan assets are as follows as of December 31, 2012:



	Pension	Other Postretirement
	%	%
Debt securities⁽¹⁾	20-30	25-35
Equity securities⁽¹⁾	65-75	60-80
Real estate funds	2-8	—
Other	0-5	0-5


(1)	For purposes of target allocation percentages and consistent with the plans' investment policy, investment funds have been allocated based on the underlying investments in debt and equity securities.

Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block]

The following table presents the fair value of plan assets, by major category, for MidAmerican Energy's defined benefit pension plan (in millions):



	Input Levels for Fair Value Measurements⁽¹⁾
	Level 1		Level 2		Level 3		Total
As of December 31, 2012
Cash equivalents	$	—	$	7	$	—	$	7
Debt securities:
United States government obligations	19		—		—		19
Corporate obligations	—		31		—		31
Municipal obligations	—		5		—		5
Agency, asset and mortgage-backed obligations	—		29		—		29
Equity securities:
United States companies	137		—		—		137
Investment funds⁽²⁾	101		288		—		389
Real estate funds	—		—		26		26
Total	$	257	$	360	$	26	$	643

As of December 31, 2011
Cash equivalents	$	—	$	9	$	—	$	9
Debt securities:
United States government obligations	6		—		—		6
Corporate obligations	—		29		—		29
Municipal obligations	—		5		—		5
Agency, asset and mortgage-backed obligations	—		35		—		35
Equity securities:
United States companies	115		—		—		115
Investment funds⁽²⁾	76		256		—		332
Real estate funds	—		—		24		24
Total	$	197	$	334	$	24	$	555


(1)	Refer to Note 14 for additional discussion regarding the three levels of the fair value hierarchy.


(2)	Investment funds are comprised of mutual funds and collective trust funds. These funds consist of equity and debt securities of approximately 74% and 26%, respectively, for 2012 and 77% and 23%, respectively, for 2011. Additionally, these funds are invested in United States and international securities of approximately 77% and 23%, respectively, for 2012 and 79% and 21%, respectively, for 2011.

The following table presents the fair value of plan assets, by major category, for MidAmerican Energy's defined benefit other postretirement plans (in millions):



	Input Levels for Fair Value Measurements⁽¹⁾
	Level 1		Level 2		Level 3		Total
As of December 31, 2012
Cash equivalents	$	2	$	—	$	—	$	2
Debt securities:
United States government obligations	4		—		—		4
Corporate obligations	—		9		—		9
Municipal obligations	—		32		—		32
Agency, asset and mortgage-backed obligations	—		14		—		14
Equity securities:
United States companies	102		—		—		102
Investment funds⁽²⁾	63		—		—		63
Total	$	171	$	55	$	—	$	226

As of December 31, 2011
Cash equivalents	$	6	$	—	$	—	$	6
Debt securities:
United States government obligations	6		—		—		6
Corporate obligations	—		7		—		7
Municipal obligations	—		30		—		30
Agency, asset and mortgage-backed obligations	—		12		—		12
Equity securities:
United States companies	88		—		—		88
Investment funds⁽²⁾	64		—		—		64
Total	$	164	$	49	$	—	$	213


(1)	Refer to Note 14 for additional discussion regarding the three levels of the fair value hierarchy.


(2)	Investment funds are comprised of mutual funds and collective trust funds. These funds consist of equity and debt securities of approximately 86% and 14%, respectively, for 2012 and 83% and 17%, respectively, for 2011. Additionally, these funds are invested in United States and international securities of approximately 51% and 49%, respectively, for 2012 and 59% and 41%, respectively, for 2011.

The following table presents MidAmerican Energy's assets and liabilities recognized on the Consolidated Balance Sheets and measured at fair value on a recurring basis (in millions):



	Input Levels for Fair Value Measurements
	Level 1			Level 2			Level 3			Other⁽¹⁾			Total
As of As of December 31, 2012:
Assets:
Commodity derivatives	$	1		$	22		$	7		$	(23	)	$	7
Money market mutual funds⁽²⁾	163			—			—			—			163
Debt securities:
United States government obligations	104			—			—			—			104
International government obligations	—			1			—			—			1
Corporate obligations	—			32			—			—			32
Municipal obligations	—			4			—			—			4
Agency, asset and mortgage-backed obligations	—			6			—			—			6
Auction rate securities	—			—			21			—			21
Equity securities:
United States companies	187			—			—			—			187
International companies	2			—			—			—			2
Investment funds	1			—			—			—			1
	$	458		$	65		$	28		$	(23	)	$	528

Liabilities - commodity derivatives	$	(10	)	$	(90	)	$	(7	)	$	30		$	(77	)

As of As of December 31, 2011:
Assets:
Commodity derivatives	$	1		$	47		$	26		$	(45	)	$	29
Debt securities:
United States government obligations	89			—			—			—			89
International government obligations	—			1			—			—			1
Corporate obligations	—			30			—			—			30
Municipal obligations	—			12			—			—			12
Agency, asset and mortgage-backed obligations	—			7			—			—			7
Auction rate securities	—			—			16			—			16
Equity securities:
United States companies	166			—			—			—			166
International companies	1			—			—			—			1
	$	257		$	97		$	42		$	(45	)	$	351

Liabilities - commodity derivatives	$	(37	)	$	(148	)	$	(4	)	$	78		$	(111	)


(1)	Represents netting under master netting arrangements and a net cash collateral receivable of $7 million and $33 million as of December 31, 2012 and 2011, respectively.


(2)	Amounts are included in cash and cash equivalents and investments and nonregulated property, net on the Consolidated Balance Sheets. The fair value of these money market mutual funds approximates cost.

Schedule of Level Three Defined Benefit Plan Assets Roll Forward [Table Text Block]

The following table reconciles the beginning and ending balances of MidAmerican Energy's pension plan assets measured at fair value using significant Level 3 inputs for the years ended December 31, (in millions):



	Real Estate Funds
	2012		2011		2010

Beginning balance	$	24	$	17	$	15
Actual return on plan assets still held at period end	2		4		2
Purchases and sales	—		3		—
Ending balance	$	26	$	24	$	17