Represents the entity's cost of debt, expressed as a percentage, used as an input to measure fair value.

No definition available.

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- Definition

Represents the entity's cost of equity, expressed as a percentage, used as an input to measure fair value.

+ References

No definition available.

+ Details

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- Definition

Represents the percentage of reasonable implied control premium.

+ References

No definition available.

+ Details

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- Definition

Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (bbb)

-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

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- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

+ Details

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- Definition

Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 2

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13854-109267

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 45

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-Name Accounting Standards Codification

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-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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Goodwill, Customer Relationships and Other Intangible Assets (Details 3) (USD $) In Millions, unless otherwise specified	3 Months Ended	12 Months Ended
	Sep. 30, 2014	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Jan. 31, 2013	Jan. 03, 2013
Finite-Lived Intangible Assets [Line Items]
Goodwill		$ 20,755us-gaap_Goodwill	$ 20,674us-gaap_Goodwill		$ 21,627us-gaap_Goodwill	$ 21,627us-gaap_Goodwill
Discount rate (percent)		6.00%us-gaap_FairValueInputsDiscountRate
Fair value inputs after tax cost of debt rate (percent)		2.90%
Fair value inputs cost of equity rate (percent)		8.20%ctl_FairValueInputsCostOfEquityRate
Percentage of reasonable implied control premium (percent)		4.30%
Impairment of goodwill	1,100us-gaap_GoodwillImpairmentLoss	0us-gaap_GoodwillImpairmentLoss	1,092us-gaap_GoodwillImpairmentLoss	0us-gaap_GoodwillImpairmentLoss
Business
Finite-Lived Intangible Assets [Line Items]
Goodwill		10,477	6,363			6,363
Impairment of goodwill			0
Consumer
Finite-Lived Intangible Assets [Line Items]
Goodwill		10,278	10,348			10,348
Impairment of goodwill			0
Wholesale
Finite-Lived Intangible Assets [Line Items]
Goodwill		0	3,274			3,274
Impairment of goodwill			0
Hosting
Finite-Lived Intangible Assets [Line Items]
Goodwill		0	689			1,642
Discount rate (percent)		11.00%
Fair value inputs after tax cost of debt rate (percent)		2.90%
Fair value inputs cost of equity rate (percent)		12.40%
Impairment of goodwill			$ 1,092