The face amount of the over-allotment sold during a debt issuance.

No definition available.

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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 55
-Paragraph 8
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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 FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
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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.

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- 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
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- Definition

Face (par) amount of the original debt instrument that was repurchased.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Carrying value as of the balance sheet date of [accrued] interest payable on all forms of debt, including trade payables, that has been incurred and is unpaid. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Current Liabilities
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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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+ Details

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Balance Type:	credit
Period Type:	instant

- 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))
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The amount for notes payable (written promise to pay), due to related parties. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(k)(1))
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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

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

- Definition

Weighted average interest rate of short-term debt outstanding.

+ 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))
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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Details

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- Details

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Balance Type:
Period Type:

- Details

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- Details

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Long-Term Debt and Revolving Promissory Note (Details 2) - USD ($) $ in Millions	May 05, 2017	Apr. 28, 2017	May 08, 2017	May 04, 2017	Mar. 31, 2017	Dec. 31, 2016
Long-term debt
Note payable - affiliate					$ 914	$ 914
Qwest Corporation \| Affiliated entity \| Loans payable
Long-term debt
Line of credit, maximum borrowing capacity					1,000
Note payable - affiliate					$ 914	$ 914
Weighted average interest rate (percent)					6.678%
Accrued interest payable on affiliate note payable					$ 20
Qwest Corporation \| Subsequent event \| Senior notes \| 6.5% Notes due 2017
Long-term debt
Debt instrument, repurchased face amount				$ 500
Stated interest rate (percent)				6.50%
Qwest Corporation \| Subsequent event \| Senior notes \| 7.5% Notes due 2051
Long-term debt
Debt instrument, repurchased face amount			$ 125
Stated interest rate (percent)			7.50%
Debt instrument, face amount			$ 288
Qwest Corporation \| Subsequent event \| Senior notes \| 6.75% Notes due 2057
Long-term debt
Stated interest rate (percent)		6.75%
Debt instrument, face amount		$ 660
Debt instrument, face amount of over-allotment	$ 85
Proceeds from debt, net of issuance costs	$ 638
Debt instrument, redemption, period one \| Qwest Corporation \| Subsequent event \| Senior notes \| 6.75% Notes due 2057
Long-term debt
Debt instrument, redemption, description		redeemed by Qwest Corporation, in whole or in part, on or after June 15, 2022, at a redemption price equal to 100% of the principal amount