Asset Retirement Obligations (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended	12 Months Ended
Dec. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Asset Retirement Obligation, Change in Accounting Estimate
Property, Plant and Equipment, Gross	$ 16,558	$ 17,329	$ 16,558
Selling, General and Administrative and Depreciation Expense		5,647	5,801	4,281
Selling, General and Administrative		2,376	2,450	1,770
Depreciation and Amortization		800	749	805
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Asset retirement obligation, beginning balance		55	121
Accretion expense		7	11
Liabilities settled		(6)		(4)
Asset Retirement Obligation, Revision of Estimate	(73)	0
Effect of foreign currency rate change		0	0
Asset retirement obligation, ending balance	55	56	55	121
Asset Retirement Obligation Change in Estimate
Asset Retirement Obligation, Change in Accounting Estimate
Property, Plant and Equipment, Gross	(24)		(24)
Selling, General and Administrative and Depreciation Expense			(49)
Selling, General and Administrative	(47)		(47)
Depreciation and Amortization	(2)		(2)
Earnings Per Share, Basic and Diluted Changes in Accounting Estimates			$ 0.23
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Asset Retirement Obligation, Revision of Estimate			(73)
Asset Retirement Obligation, Change in Estimate Right-of-way
Asset Retirement Obligation, Change in Accounting Estimate
Selling, General and Administrative			$ (21)
Earnings Per Share, Basic and Diluted Changes in Accounting Estimates			$ 0.10

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Earnings Per Share, Basic and Diluted Changes in Accounting Estimates. The amount of net income or loss for the period due to changes in estimates.

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- Definition

The carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 410

-SubTopic 20

-Section 50

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-Publisher FASB

-Name Accounting Standards Codification

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- Definition

Amount of accretion expense recognized during the period that is associated with an asset retirement obligation. Accretion expense measures and incorporates changes due to the passage of time into the carrying amount of the liability.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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Amount of the Increase or Decrease in the amount of asset retirement obligations for the period associated with foreign currency translation (to the extent that the entity accounts for the foreign currency effects as a separate component of the change in the liability).

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Amount of asset retirement obligations settled, or otherwise disposed of, during the period. This may include asset retirement obligations transferred to third parties associated with the sale of a long-lived asset.

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Amount of the Increase or Decrease in the amount of the asset retirement obligation during the current period for changes in the amount or timing of the estimated cash flows associated with the settlement of the obligation.

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Total costs of sales and operating expenses for the period.

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The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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The aggregate total costs related to selling a firm's product and services, as well as all other general and administrative expenses. Direct selling expenses (for example, credit, warranty, and advertising) are expenses that can be directly linked to the sale of specific products. Indirect selling expenses are expenses that cannot be directly linked to the sale of specific products, for example telephone expenses, Internet, and postal charges. General and administrative expenses include salaries of non-sales personnel, rent, utilities, communication, etc.

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