Retirement Benefits and Trusteed Assets (Tables)

12 Months Ended

Dec. 31, 2011

Defined Contribution Pension and Other Postretirement Plans Disclosure [Abstract]

Schedule of Net Benefit Costs [Table Text Block]

	2011			2010			2009
	(In millions)
Service cost	$	69		$	64		$	52
Interest cost	202			202			203
Expected return on plan assets	(246		)	(258		)	(255		)
Amortization of:
Net actuarial loss	142			100			52
Prior service cost	3			4			6
Special termination benefits	2			—			—
Net pension cost	$	172		$	112		$	58

Schedule of Defined Benefit Plan Amounts Recognized in Other Comprehensive Income (Loss) [Table Text Block]

	2011			2010
	(In millions)
Other changes in plan assets and benefit obligations recognized in Regulatory assets and Other comprehensive income
Net actuarial loss	$	619		$	166
Amortization of net actuarial loss	(142		)	(100		)
Amortization of prior service cost	(3		)	(4		)
Total recognized Regulatory assets and Other comprehensive income	$	474		$	62
Total recognized in net periodic pension cost, Regulatory assets and Other comprehensive income	$	646		$	174
Estimated amounts to be amortized from Regulatory assets and Accumulated other comprehensive income into net periodic benefit cost during next fiscal year
Net actuarial loss	$	171		$	133
Prior service cost	—			3

Schedule of Defined Benefit Plans Disclosures [Table Text Block]

	2011			2010
	(In millions)
Accumulated benefit obligation, end of year	$	3,881		$	3,521
Change in projected benefit obligation
Projected benefit obligation, beginning of year	$	3,785		$	3,436
Consolidation of VIEs	—			82
Service cost	69			64
Interest cost	202			202
Actuarial loss	355			216
Special termination benefits	2			—
Benefits paid	(218		)	(215		)
Projected benefit obligation, end of year	$	4,195		$	3,785
Change in plan assets
Plan assets at fair value, beginning of year	$	2,913		$	2,549
Consolidation of VIEs	—			64
Actual return on plan assets	(18		)	309
Company contributions	209			206
Benefits paid	(218		)	(215		)
Plan assets at fair value, end of year	$	2,886		$	2,913
Funded status of the plans	$	(1,309	)	$	(872	)
Amount recorded as:
Current liabilities	$	(11	)	$	(6	)
Noncurrent liabilities	(1,298		)	(866		)
	$	(1,309	)	$	(872	)
Amounts recognized in Accumulated other comprehensive loss, pre-tax
Net actuarial loss	$	202		$	195
Prior service (credit)	(3		)	(4		)
	$	199		$	191
Amounts recognized in Regulatory assets (see Note 11)
Net actuarial loss	$	2,201		$	1,730
Prior service cost	7			12
	$	2,208		$	1,742

Assumptions Used to Determine the Projected Benefit Obligation and Net Pension Cost [Table Text Block]

Assumptions used in determining the projected benefit obligation and net pension costs are listed below:

	2011		2010		2009
Projected benefit obligation
Discount rate	5.00	%	5.50	%	5.90	%
Rate of compensation increase	4.20	%	4.00	%	4.00	%
Net pension costs
Discount rate	5.50	%	5.90	%	6.90	%
Rate of compensation increase	4.00	%	4.00	%	4.00	%
Expected long-term rate of return on plan assets	8.50	%	8.75	%	8.75	%

Schedule of Expected Benefit Payments [Table Text Block]

	(In millions)
2012	$	240
2013	239
2014	244
2015	253
2016	260
2017-2021	1,439
	$	2,675

Schedule of Allocation of Plan Assets [Table Text Block]

Target allocations for plan assets as of December 31, 2011 are listed below:

U.S. Large Cap Equity Securities	22	%
U.S. Small Cap and Mid Cap Equity Securities	5
Non U.S. Equity Securities	20
Fixed Income Securities	25
Hedge Funds and Similar Investments	20
Private Equity and Other	8
	100	%

Pension Plans Fair Value Hierachy Level [Table Text Block]

Fair Value Measurements at December 31, 2011(a)

	Level 1		Level 2		Level 3		Balance at December 31, 2011
	(In millions)
Asset Category:
Short-term investments (b)	$	—	$	33	$	—	$	33
Equity securities
U.S. Large Cap (c)	640		40		—		680
U.S. Small/Mid Cap (d)	159		5		—		164
Non U.S (e)	392		114		—		506
Fixed income securities (f)	88		703		—		791
Hedge Funds and Similar Investments (g)	190		58		296		544
Private Equity and Other (h)	—		—		168		168
Total	$	1,469	$	953	$	464	$	2,886

Fair Value Measurements at December 31, 2010(a)

	Level 1		Level 2		Level 3		Balance at December 31, 2010
	(In millions)
Asset Category:
Short-term investments (b)	$	—	$	34	$	—	$	34
Equity securities
U.S. Large Cap (c)	686		38		—		724
U.S. Small/Mid Cap (d)	181		8		—		189
Non U.S (e)	285		222		—		507
Fixed income securities (f)	61		658		—		719
Hedge Funds and Similar Investments (g)	189		73		304		566
Private Equity and Other (h)	—		—		174		174
Total	$	1,402	$	1,033	$	478	$	2,913

Schedule of Effect of Significant Unobservable Inputs, Changes in Plan Assets [Table Text Block]

Fair Value Measurements Using Significant Unobservable Inputs (Level 3):

	Hedge Funds and Similar Investments			Private Equity and Other			Total
	(In millions)
Beginning Balance at January 1, 2011	$	304		$	174		$	478
Total realized/unrealized gains (losses):
Realized gains (losses)	(4		)	6			2
Unrealized gains (losses)	1			(30		)	(29		)
Purchases, sales and settlements:
Purchases	64			23			87
Sales	(69		)	(5		)	(74		)
Ending Balance at December 31, 2011	$	296		$	168		$	464
The amount of total gains (losses) for the period attributable to the change in unrealized gains or losses related to assets still held at the end of the period	$	4		$	(28	)	$	(24	)

	Hedge Funds and Similar Investments			Private Equity and Other			Total
	(In millions)
Beginning Balance at January 1, 2010	$	484		$	160		$	644
Total realized/unrealized gains (losses)	51			23			74
Purchases, sales and settlements	(231		)	(9		)	(240		)
Ending Balance at December 31, 2010	$	304		$	174		$	478
The amount of total gains (losses) for the period attributable to the change in unrealized gains or losses related to assets still held at the end of the period	$	29		$	13		$	42

Schedule of Net Postretirement Costs [Table Text Block]

Net postretirement cost includes the following components:

	2011			2010			2009
	(In millions)
Service cost	$	64		$	61		$	59
Interest cost	121			125			133
Expected return on plan assets	(94		)	(74		)	(55		)
Amortization of:
Net loss	55			54			72
Prior service (credit)	(26		)	(4		)	(6		)
Net transition obligation	2			2			2
Net postretirement cost	$	122		$	164		$	205

Schedule of Postretirement Plan Amounts Recognized in Other Comprehensive Income [Table Text Block]

	2011			2010
	(In millions)
Other changes in plan assets and APBO recognized in Regulatory assets and Other comprehensive income
Net actuarial loss	$	195		$	93
Amortization of net actuarial loss	(55		)	(54		)
Prior service credit	(4		)	(79		)
Amortization of prior service credit	26			4
Amortization of transition asset	(2		)	(2		)
Total recognized in Regulatory assets and Other comprehensive income	$	160		$	(38	)
Total recognized in net periodic pension cost, Regulatory assets and Other comprehensive income	$	282		$	126
Estimated amounts to be amortized from Regulatory assets and Accumulated other comprehensive income into net periodic benefit cost during next fiscal year
Net actuarial loss	$	78		$	59
Prior service credit	$	(27	)	$	(26	)
Net transition obligation	$	2		$	2

Schedule of Other Postretirement Benefit Plans Disclosures [Table Text Block]

The following table reconciles the obligations, assets and funded status of the plans including amounts recorded as accrued postretirement cost in the Consolidated Statements of Financial Position at December 31:

	2011			2010
	(In millions)
Change in accumulated postretirement benefit obligation
Accumulated postretirement benefit obligation, beginning of year	$	2,305		$	2,151
Consolidation of VIEs	—			21
Service cost	64			61
Interest cost	121			125
Plan amendments	(4		)	(79		)
Actuarial loss	80			127
Medicare Part D subsidy	6			7
Benefits paid	(102		)	(108		)
Accumulated postretirement benefit obligation, end of year	$	2,470		$	2,305
Change in plan assets
Plan assets at fair value, beginning of year	$	1,029		$	864
Actual return on plan assets	(22		)	108
Company contributions	111			160
Benefits paid	(133		)	(103		)
Plan assets at fair value, end of year	$	985		$	1,029
Funded status, end of year	$	(1,485	)	$	(1,276	)
Amount recorded as:
Current liabilities	$	(1	)	$	(1	)
Noncurrent liabilities	$	(1,484	)	$	(1,275	)
	$	(1,485	)	$	(1,276	)
Amounts recognized in Accumulated other comprehensive loss, pre-tax
Net actuarial loss	$	47		$	46
Prior service credit	(20		)	(28		)
Net transition asset	(1		)	(2		)
	$	26		$	16
Amounts recognized in Regulatory assets (See Note 11)
Net actuarial loss	$	835		$	692
Prior service cost	(60		)	(74		)
Net transition obligation	3			6
	$	778		$	624

Assumptions used to Determine Projected Benefit Obligations and Net OPEB Costs [Table Text Block]

Assumptions used in determining the projected benefit obligation and net benefit costs are listed below:

	2011		2010		2009
Projected benefit obligation
Discount rate	5.00	%	5.50	%	5.90	%
Net benefit costs
Discount rate	5.50	%	5.90	%	6.90	%
Expected long-term rate of return on plan assets	8.75	%	8.75	%	8.75	%
Health care trend rate pre- and post- 65	7.00	%	7.00	%	7.00	%
Ultimate health care trend rate	5.00	%	5.00	%	5.00	%
Year in which ultimate reached	2019		2016		2016

Schedule of Expected Benefit Payments OPEB [Table Text Block]

	(In millions)
2012	$	109
2013	116
2014	124
2015	132
2016	142
2017 — 2021	839
	$	1,462

Schedule of Allocation of Plan Assets OPEB [Table Text Block]

Target allocations for plan assets as of December 31, 2011 are listed below:

U.S. Large Cap Equity Securities	22	%
Non U.S. Equity Securities	20
Fixed Income Securities	25
Hedge Funds and Similar Investments	20
Private Equity and Other	13
	100	%

Other Postretirement Benefit Plans Hierachy Level [Table Text Block]

Fair Value Measurements at December 31, 2011(a)

	Level 1		Level 2		Level 3		Balance at December 31, 2011
	(In millions)
Asset Category:
Short-term investments (b)	$	—	$	13	$	—	$	13
Equity securities:
U.S. Large Cap (c)	175		15		—		190
U.S. Small/Mid Cap (d)	70		6		—		76
Non U.S (e)	176		14		—		190
Fixed income securities (f)	24		236		—		260
Hedge Funds and Similar Investments (g)	80		21		95		196
Private Equity and Other (h)	—		—		60		60
Total	$	525	$	305	$	155	$	985

Fair Value Measurements at December 31, 2010(a)

	Level 1		Level 2		Level 3		Balance at December 31, 2010
	(In millions)
Asset Category:
Short-term investments (b)	$	—	$	8	$	—	$	8
Equity securities
U.S. Large Cap (c)	126		62		—		188
U.S. Small/Mid Cap (d)	60		58		—		118
Non U.S (e)	79		122		—		201
Fixed income securities (f)	4		252		—		256
Hedge Funds and Similar Investments (g)	76		48		79		203
Private Equity and Other (h)	—		—		55		55
Total	$	345	$	550	$	134	$	1,029

Schedule of Effect of Significant Unobservable Inputs, Changes in Plan Assets OPEB [Table Text Block]

Fair Value Measurements Using Significant Unobservable Inputs (Level 3):

	Hedge Funds and Similar Investments			Private Equity and Other			Total
	(In millions)
Beginning Balance at January 1, 2011	$	79		$	55		$	134
Total realized/unrealized gains (losses):
Realized gains (losses)	(1		)	2			1
Unrealized gains (losses)	2			(22		)	(20		)
Purchases, sales and settlements:
Purchases	68			48			116
Sales	(53		)	(23		)	(76		)
Ending Balance at December 31, 2011	$	95		$	60		$	155
The amount of total gains (losses) for the period attributable to the change in unrealized gains or losses related to assets still held at the end of the period	$	5		$	(16	)	$	(11	)

	Hedge Funds and Similar Investments			Private Equity and Other		Total
	(In millions)
Beginning Balance at January 1, 2010	$	92		$	46	$	138
Total realized/unrealized gains	10			8		18
Purchases, sales and settlements	(23		)	1		(22		)
Ending Balance at December 31, 2010	$	79		$	55	$	134
The amount of total gains (losses) for the period attributable to the change in unrealized gains or losses related to assets still held at the end of the period	$	6		$	7	$	13