Segment Information (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014 segment	Sep. 30, 2013
Segment information
Number of operating segments (segments)			4
Operating revenue	$ 4,514	$ 4,515	$ 13,593	$ 13,553
Expenses	3,895	5,200	11,666	12,741
Total segment income	619	(685)	1,927	812
Operating segments
Segment information
Operating revenue	4,264	4,267	12,836	12,799
Expenses	2,161	2,089	6,378	6,056
Total segment income	2,103	2,178	6,458	6,743
Margin percentage (percent)	49.00%	51.00%	50.00%	53.00%
Consumer
Segment information
Operating revenue	1,491	1,503	4,500	4,508
Expenses	611	605	1,793	1,728
Total segment income	880	898	2,707	2,780
Margin percentage (percent)	59.00%	60.00%	60.00%	62.00%
Intersegment expense reclassification adjustment		25		67
Business
Segment information
Operating revenue	1,569	1,544	4,692	4,574
Expenses	997	932	2,935	2,701
Total segment income	572	612	1,757	1,873
Margin percentage (percent)	36.00%	40.00%	37.00%	41.00%
Intersegment expense reclassification adjustment		(25)		(67)
Wholesale
Segment information
Operating revenue	843	878	2,571	2,694
Expenses	285	293	844	868
Total segment income	558	585	1,727	1,826
Margin percentage (percent)	66.00%	67.00%	67.00%	68.00%
Hosting
Segment information
Operating revenue	361	342	1,073	1,023
Expenses	268	259	806	759
Total segment income	93	83	267	264
Margin percentage (percent)	26.00%	24.00%	25.00%	26.00%
Intersegment expense reclassification adjustment		$ (16)		$ (55)

The amount of a reclassification adjustment made to prior period segment expense amounts.

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- Definition

Represents the operating margin assigned to segments for the period.

+ References

No definition available.

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- Definition

Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

+ References

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- Definition

Generally recurring costs associated with normal operations except for the portion of these expenses which can be clearly related to production and included in cost of sales or services. Includes selling, general and administrative expense.

+ References

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- Definition

The net result for the period of deducting operating expenses from operating revenues.

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- Definition

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.1)

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 1

-Article 5

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