Products and Services Revenues (Details) $ in Millions	3 Months Ended
Mar. 31, 2017 USD ($) category	Mar. 31, 2016 USD ($)
Products and Services Revenues
Operating revenues	$ 2,162	$ 2,253
Number of categories of products and services (categories) \| category	3
USF surcharges included in operating revenues	$ 33	38
Number of reportable segments (segments)	1
Strategic services
Products and Services Revenues
Operating revenues	$ 663	670
Legacy services
Products and Services Revenues
Operating revenues	744	844
Affiliates and other services
Products and Services Revenues
Operating revenues	$ 755	739
Low-bandwidth data services \| Restatement adjustment \| Strategic services
Products and Services Revenues
Operating revenues		(189)
Low-bandwidth data services \| Restatement adjustment \| Legacy services
Products and Services Revenues
Operating revenues		$ 189

Represents the number of categories in which the entity categorizes the products and services.

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- Definition

Represents the taxes and surcharges on revenues from universal service funds (USF), which are included in operating revenues and expenses.

+ References

No definition available.

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

+ References

No definition available.

+ Details

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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=63488584&loc=d3e20235-122688

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