Percentage of principal amount of debt redeemable during a specified redemption period.

No definition available.

Name:	ctl_DebtInstrumentRedemptionPricePercentageofPrincipalAmountRedeemable
Namespace Prefix:	ctl_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- 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

Name:	us-gaap_DebtInstrumentRedemptionDescription
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- 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

Name:	us-gaap_DebtInstrumentRedemptionLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

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

+ References

+ Details

Name:	us-gaap_DebtInstrumentRedemptionPricePercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_SeniorNotesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=ctl_Notes6.625due2055Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentRedemptionPeriodAxis=us-gaap_DebtInstrumentRedemptionPeriodOneMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	dei_LegalEntityAxis=ctl_QwestCorporationMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=ctl_Notes5.625percentdue2025Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	dei_LegalEntityAxis=us-gaap_ParentCompanyMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentRedemptionPeriodAxis=us-gaap_DebtInstrumentRedemptionPeriodTwoMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentRedemptionPeriodAxis=us-gaap_DebtInstrumentRedemptionPeriodThreeMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentRedemptionPeriodAxis=us-gaap_DebtInstrumentRedemptionPeriodFourMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=ctl_Notes6.875percentdue2054Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_SubsequentEventTypeAxis=us-gaap_SubsequentEventMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=ctl_A7.00Notesdue2056Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Long-Term Debt and Credit Facilities Long-Term Debt and Credit Facilities (Details 3) - Senior notes	Jan. 31, 2016	Sep. 21, 2015	Mar. 19, 2015	Sep. 29, 2014
6.625% Notes due 2055 \| Debt Instrument, Redemption, Period One [Member] \| Qwest Corporation
Debt Instrument, Redemption [Line Items]
Debt Instrument, Redemption Price, Percentage		100.00%
5.625% Notes due 2025 \| Debt Instrument, Redemption, Period One [Member] \| CenturyLink, Inc.
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
5.625% Notes due 2025 \| Debt Instrument, Redemption, Period Two [Member] \| CenturyLink, Inc.
Debt Instrument, Redemption [Line Items]
Debt Instrument, Redemption, Description			redeem the Notes at par
5.625% Notes due 2025 \| Debt Instrument, Redemption, Period Three [Member] \| CenturyLink, Inc.
Debt Instrument, Redemption [Line Items]
Debt Instrument, Redemption Price, Percentage			105.625%
Debt Instrument, Redemption Price, Percentage of Principal Amount Redeemable			35.00%
5.625% Notes due 2025 \| Debt Instrument, Redemption, Period Four [Member] \| CenturyLink, Inc.
Debt Instrument, Redemption [Line Items]
Debt Instrument, Redemption Price, Percentage			101.00%
6.875% Notes due 2054 \| Debt Instrument, Redemption, Period One [Member] \| Qwest Corporation
Debt Instrument, Redemption [Line Items]
Debt Instrument, Redemption Price, Percentage				100.00%
Subsequent Event \| 7.00% Notes due 2056 \| Debt Instrument, Redemption, Period One [Member] \| Qwest Corporation
Debt Instrument, Redemption [Line Items]
Debt Instrument, Redemption Price, Percentage	100.00%