Sale Of Equipment Installment Receivables (Finance Receivables) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014
Changes In Other Assets [Line Items]
Receivables sold during period	$ 7,436	$ 4,707
Cash proceeds received	4,439	2,528
Deferred purchase price recorded	2,266	1,629
Finance Receivables, Net [Member]
Changes In Other Assets [Line Items]
Receivables sold during period	$ 6,704	$ 4,126

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- Definition

Amount of significant additions in the period in other assets (current, noncurrent, or unclassified).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.17)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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+ References

No definition available.

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