The number of lenders of the revolving line of credit.

No definition available.

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Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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- Definition

Amount of long-term debt before deduction of unamortized discount or premium. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, with initial maturities beyond one year or the normal operating cycle, if longer.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 20

-Article 5

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 16

-Article 9

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- 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 45

-Paragraph 2

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

Reference 2: 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

+ Details

Name:	us-gaap_DebtInstrumentFaceAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Details

Name:	us-gaap_DebtInstrumentLineItems
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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.19(b),22(b))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

+ Details

Name:	us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The cash inflow from additional borrowings, net of cash paid to third parties in connection with debt origination.

+ References

No definition available.

+ Details

Name:	us-gaap_ProceedsFromDebtNetOfIssuanceCosts
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

+ References

No definition available.

+ Details

Name:	us-gaap_RepaymentsOfDebt
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

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- Details

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Namespace Prefix:
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Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=us-gaap_LineOfCreditMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RangeAxis=us-gaap_MaximumMember
Namespace Prefix:
Data Type:	na
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Long-Term Debt and Credit Facilities Long-Term Debt and Credit Facilities (Details 2) (USD $) In Millions, unless otherwise specified	0 Months Ended
	Feb. 17, 2015	Mar. 19, 2015	Feb. 20, 2015	Mar. 31, 2015	Dec. 31, 2014	Feb. 15, 2015	Jan. 31, 2015
CenturyLink, Inc. \| Senior notes
Long-term Debt and Credit Facilities
Long-term debt, gross				$ 7,975	$ 7,825
CenturyLink, Inc. \| Senior notes \| Series M 5.00% Notes
Long-term Debt and Credit Facilities
Repayments of debt	350
Stated interest rate (percent)						5.00%
CenturyLink, Inc. \| Senior notes \| Notes, 5.625 percent due 2025 [Member]
Long-term Debt and Credit Facilities
Debt instrument, face amount		500
Stated interest rate (percent)		5.625%
Proceeds from debt, net of issuance costs		494
CenturyLink, Inc. \| Medium-term notes
Long-term Debt and Credit Facilities
Long-term debt, gross				374	380
Qwest Corporation \| Senior notes
Long-term Debt and Credit Facilities
Long-term debt, gross				7,311	7,311
Qwest Corporation \| Medium-term notes
Long-term Debt and Credit Facilities
Long-term debt, gross				100	0
Qwest Corporation \| Medium-term notes \| Term Loan
Long-term Debt and Credit Facilities
Debt instrument, face amount			100
Long-term debt, gross				100
Minimum \| CenturyLink, Inc. \| Senior notes
Long-term Debt and Credit Facilities
Stated interest rate (percent)				5.15%
Minimum \| Qwest Corporation \| Senior notes
Long-term Debt and Credit Facilities
Stated interest rate (percent)				6.125%
Minimum \| London Interbank Offered Rate (LIBOR) \| Qwest Corporation \| Medium-term notes \| Term Loan
Long-term Debt and Credit Facilities
Basis spread on variable rate (percent)			1.50%
Minimum \| Base Rate \| Qwest Corporation \| Medium-term notes \| Term Loan
Long-term Debt and Credit Facilities
Basis spread on variable rate (percent)			0.50%
Maximum \| CenturyLink, Inc. \| Senior notes
Long-term Debt and Credit Facilities
Stated interest rate (percent)				7.65%
Maximum \| Qwest Corporation \| Senior notes
Long-term Debt and Credit Facilities
Stated interest rate (percent)				8.375%
Maximum \| London Interbank Offered Rate (LIBOR) \| Qwest Corporation \| Medium-term notes \| Term Loan
Long-term Debt and Credit Facilities
Basis spread on variable rate (percent)			2.50%
Maximum \| Base Rate \| Qwest Corporation \| Medium-term notes \| Term Loan
Long-term Debt and Credit Facilities
Basis spread on variable rate (percent)			1.50%
Line of credit \| CenturyLink, Inc. \| Line of credit
Long-term Debt and Credit Facilities
Line of credit facility, maximum borrowing capacity							$ 100
Lenders of revolving line of credit, number							1