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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Balance Type:	credit
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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

+ Details

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- Definition

Disclosure of the extent of enterprise reliance on its major customers. For example, includes revenues from transactions with a single external customer amounting to 10 percent or more of the entity's revenues, the total amount of revenues from each such customer, and the identity of the segment or segments reporting the revenues. A group of entities that the entity knows to be under common control generally will be considered a single customer for inclusion in this item. The federal government, a state government, a local government (for example, a county or municipality), or a foreign government each will generally be considered as a single customer for inclusion in this item.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 42
-URI http://asc.fasb.org/extlink&oid=68060357&loc=d3e9054-108599

+ Details

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Balance Type:	na
Period Type:	duration

- Details

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Namespace Prefix:
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- Details

Name:	us-gaap_ProductOrServiceAxis=ctq_LegacyServicesMember
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Data Type:	na
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Period Type:

- Details

Name:	us-gaap_ProductOrServiceAxis=ctq_AffiliatesAndOtherServicesMember
Namespace Prefix:
Data Type:	na
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- Details

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- Details

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Products and Services Revenues (Details) $ in Millions	3 Months Ended		9 Months Ended
Products and Services Revenues (Details) $ in Millions	Sep. 30, 2016 USD ($)	Sep. 30, 2015 USD ($)	Sep. 30, 2016 USD ($) category segment	Sep. 30, 2015 USD ($)
Products and Services Revenues
Operating revenues	$ 2,226	$ 2,287	$ 6,702	$ 6,726
Number of categories of products and services (categories) \| category			3
USF surcharges included in operating revenues	37	37	$ 113	111
Number of reportable segments (segments) \| segment			1
Individual customers accounting for more than 10% of total operating revenues			We do not have any single external customer that provides more than 10% of our total consolidated operating revenues.
Strategic services
Products and Services Revenues
Operating revenues	674	651	$ 2,018	1,942
Legacy services
Products and Services Revenues
Operating revenues	796	890	2,455	2,723
Affiliates and other services
Products and Services Revenues
Operating revenues	$ 756	746	$ 2,229	2,061
Low-bandwidth data services \| Restatement adjustment \| Strategic services
Products and Services Revenues
Operating revenues		(201)		(627)
Low-bandwidth data services \| Restatement adjustment \| Legacy services
Products and Services Revenues
Operating revenues		$ 201		$ 627