Income, Sales-Based And Other Taxes (Deferred Income Tax (Assets) And Liabilities By Balance Sheet Classification) (Details) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014
Income, Sales-Based And Other Taxes [Abstract]
Other current assets	$ (1,329)	$ (2,001)
Other assets, including intangibles, net	(3,421)	(3,955)
Accounts payable and accrued liabilities	546	451
Deferred income tax liabilities	36,818	39,230
Net deferred tax liabilities	$ 32,614	$ 33,725

Amount, after deferred tax asset, of deferred tax liability attributable to taxable differences, netted by jurisdiction.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32537-109319

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 45
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=37586315&loc=d3e31931-109318

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 45
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=37586315&loc=d3e31931-109318

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 45
-Paragraph 9
-URI http://asc.fasb.org/extlink&oid=37586315&loc=d3e31958-109318

Reference 3: http://www.xbrl.org/2003/role/presentationRef
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-Topic 740
-SubTopic 10
-Section 45
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=37586315&loc=d3e31917-109318

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