Products and Services Revenues (Details) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2017 USD ($)	Sep. 30, 2016 USD ($)	Sep. 30, 2017 USD ($)	Sep. 30, 2016 USD ($)
Products and Services Revenues
Number of categories of products and services (categories)			3
Operating revenues	$ 2,141	$ 2,226	$ 6,436	$ 6,702
USF surcharges included in operating revenues	33	37	$ 100	113
Number of reportable segments (segments)			1
Strategic services
Products and Services Revenues
Operating revenues	679	676	$ 2,011	2,023
Legacy services
Products and Services Revenues
Operating revenues	699	794	2,160	2,450
Affiliates and other services
Products and Services Revenues
Operating revenues	$ 763	$ 756	$ 2,265	$ 2,229

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

No definition available.

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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.

+ Details

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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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- Details

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