v2.4.0.6

Income Taxes (Tables)

12 Months Ended

Dec. 31, 2011

Income Taxes [Abstract]

Schedule Of Income Tax Expense (Benefit)

	Year Ended December 31,
	2011	2010	2009
	(In millions)
Current income tax (benefit) expense:
U.S. federal	$       (143)	$         244	$           45
Various states	20	16	18
Canada and various provinces	(20)	256	178
Total current tax (benefit) expense	(143)	516	241
Deferred income tax expense (benefit):
U.S. federal	1,986	781	(1,846)
Various states	95	21	(111)
Canada and various provinces	218	(83)	(57)
Total deferred tax expense (benefit)	2,299	719	(2,014)
Total income tax expense (benefit)	$     2,156	$     1,235	$    (1,773)

Schedule Of Effective Income Tax Reconciliation

	Year Ended December 31,
	2011	2010	2009
	(In millions)
Expected income tax expense (benefit) based on U.S. statutory tax   rate of 35%	$     1,502	$     1,249	$    (1,584)
Assumed repatriations.	725	144	55
State income taxes	70	31	(99)
Taxation on Canadian operations	(91)	(60)	(31)
Other	(50)	(129)	(114)
Total income tax expense (benefit)	$     2,156	$     1,235	$    (1,773)

Schedule Of Deferred Tax Assets And Liabilities

	December 31,
	2011	2010
Deferred tax assets:	(In millions)
Net operating loss carryforwards	$        222	$        159
Asset retirement obligations	447	494
Pension benefit obligations	130	133
Other	117	171
Total deferred tax assets	916	957
Deferred tax liabilities:
Property and equipment	(4,475)	(3,130)
Fair value of financial instruments	(218)	(70)
Long-term debt	(185)	(198)
Taxes on unremitted foreign earnings (	(936)	(211)
Other	(27)	(20)
Total deferred tax liabilities	(5,841)	(3,629)
Net deferred tax liability	$    (4,925)	$    (2,672)

Schedule Of Changes In Unrecognized Tax Benefits

	December 31,
	2011	2010
	(In millions)
Balance at beginning of year	$        194	$        272
Tax positions taken in prior periods	(3)	40
Tax positions taken in current year	27	5
Accrual of interest related to tax positions taken	(7)	9
Lapse of statute of limitations	(41)	(5)
Settlements	(5)	(129)
Foreign currency translation	—	2
Balance at end of year	$        165	$        194

Summary Of The Tax Years By Jurisdiction That Remain Subject To Examination By Taxing Authorities

Jurisdiction	Tax Years Open
U.S. federal	2008-2011
Various U.S. states	2007-2011
Canada federal	2003-2011
Various Canadian provinces	2003-2011

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Tabular disclosure of the components of income tax expense attributable to continuing operations for each year presented including, but not limited to: current tax expense (benefit), deferred tax expense (benefit), investment tax credits, government grants, the benefits of operating loss carryforwards, tax expense that results from allocating certain tax benefits either directly to contributed capital or to reduce goodwill or other noncurrent intangible assets of an acquired entity, adjustments of a deferred tax liability or asset for enacted changes in tax laws or rates or a change in the tax status of the entity, and adjustments of the beginning-of-the-year balances of a valuation allowance because of a change in circumstances that causes a change in judgment about the realizability of the related deferred tax asset in future years.

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Tabular disclosure of the components of net deferred tax asset or liability recognized in an entity's statement of financial position, including the following: the total of all deferred tax liabilities, the total of all deferred tax assets, the total valuation allowance recognized for deferred tax assets.

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Tabular disclosure of the reconciliation using percentage or dollar amounts of the reported amount of income tax expense attributable to continuing operations for the year to the amount of income tax expense that would result from applying domestic federal statutory tax rates to pretax income from continuing operations.

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Tabular disclosure of tax positions taken in the tax returns filed or to be filed for which it is more likely than not that the tax position will not be sustained upon examination by taxing authorities (i.e., uncertain tax positions) and other types of income tax contingencies, including: (1) the policy on classification of interest and penalties; (2) a tabular reconciliation of the total amounts of unrecognized tax benefits at the beginning and end of the period; the total amount(s) of: (3) unrecognized tax benefits that, if recognized, would affect the effective tax rate, and (4) interest and penalties recognized in each of the income statement and balance sheet; (5) for positions for which it is reasonably possible that the total amounts unrecognized will significantly change within 12 months of the reporting date the: (i) nature of the uncertainty, (ii) nature of the event that could occur that would cause the change, and (iii) an estimate of the range of the reasonably possible change or a statement that an estimate of the range cannot be made; and (6) a description of tax years that remain subject to examination by major tax jurisdictions.

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Tabular disclosure of income tax examinations that an enterprise is currently subject to or that have been completed in the current period typically including a description of the examination, the jurisdiction conducting the examination, the tax year(s) under examination, the likelihood of an unfavorable settlement, the range of possible losses, the liability recorded, the increase or decrease in the liability from the prior period, and any penalties and interest that have been recorded.

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