Income Taxes (Reconciliation of Unrecognized Tax Benefits) (Details) (USD $) In Millions, unless otherwise specified	9 Months Ended
Sep. 30, 2014
Income Taxes [Abstract]
Beginning balance	$ 1,701
Additions based on tax positions related to the current year	54
Additions based on tax positions related to prior years	31
Reductions for tax positions of prior years	(168)
Reductions due to expiration of statutes of limitations	(436)
Settlements with taxing authorities	(15)
Ending balance	$ 1,167

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Amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Unrecognized Tax Benefit

-URI http://asc.fasb.org/extlink&oid=6527854

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

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-Section 50

-Paragraph 15A

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Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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

-Publisher FASB

-Name Accounting Standards Codification

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Amount of decrease in unrecognized tax benefits resulting from settlements with taxing authorities.

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Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

+ References

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

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Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations.

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