Percentage of principal amount of debt that may be redeemed.

No definition available.

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Namespace Prefix:	ctl_
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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 55

-Paragraph 8

-URI http://asc.fasb.org/extlink&oid=34725769&loc=d3e28878-108400

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Description of debt redemption features under terms of the debt agreement.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 470

-Section 50

-Paragraph 3

-Subparagraph e

-URI http://asc.fasb.org/extlink&oid=6479336&loc=d3e64711-112823

+ 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

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

+ References

+ Details

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- Details

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- Details

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Long-Term Debt and Credit Facilities Long-Term Debt and Credit Facilities (Details 3) - Senior notes - USD ($) $ in Millions	Sep. 21, 2015	Mar. 19, 2015	Sep. 30, 2015
CenturyLink, Inc. \| 5.625% Notes due 2025
Debt Instrument, Redemption [Line Items]
Debt instrument, face amount		$ 500
CenturyLink, Inc. \| 5.625% Notes due 2025 \| Debt instrument, redemption, period one
Debt Instrument, Redemption [Line Items]
Debt Instrument, redemption, description		greater of 100% of the principal amount of the Notes or the sum of the present value of the remaining scheduled payments of principal and interest on the Notes, discounted to the redemption date in the manner described in the Notes
CenturyLink, Inc. \| 5.625% Notes due 2025 \| Debt instrument, redemption, period two
Debt Instrument, Redemption [Line Items]
Debt Instrument, redemption, description		redeem the Notes at par
CenturyLink, Inc. \| 5.625% Notes due 2025 \| Debt instrument, redemption, period three
Debt Instrument, Redemption [Line Items]
Debt instrument, redemption price, percentage of principal amount (percent)		35.00%
Debt instrument, redemption price, percentage (percent)		105.625%
CenturyLink, Inc. \| 5.625% Notes due 2025 \| Debt instrument, redemption, period four
Debt Instrument, Redemption [Line Items]
Debt instrument, redemption price, percentage (percent)		101.00%
Qwest Corporation \| 6.625% Notes due 2055
Debt Instrument, Redemption [Line Items]
Debt instrument, face amount	$ 400		$ 10
Qwest Corporation \| 6.625% Notes due 2055 \| Debt instrument, redemption, period one
Debt Instrument, Redemption [Line Items]
Debt instrument, redemption price, percentage (percent)	100.00%