Income Taxes (Unrecognized Tax Benefits Reconciliation) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Reconciliation of the beginning and ending amounts of unrecognized tax benefits
Unrecognized Tax Benefits	$ 3,223us-gaap_UnrecognizedTaxBenefits	$ 3,106us-gaap_UnrecognizedTaxBenefits
Additions for tax positions of current year	61	79
Reductions for tax positions of the current year	(2)	(1)
Additions for tax positions of prior years	483	657
Reductions for tax positions of prior years	(531)	(617)
Settlements with tax authorities	(179)	(1)
Expiration on the statute of limitations	0	0
Unrecognized Tax Benefits	$ 3,055us-gaap_UnrecognizedTaxBenefits	$ 3,223us-gaap_UnrecognizedTaxBenefits

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

+ References

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-Publisher FASB

-Name Accounting Standards Codification

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

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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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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.

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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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