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

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

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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

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

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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.

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

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

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

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Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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Amount of interest capitalized during the period.

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Total interest costs incurred during the period and either capitalized or charged against earnings.

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Amount of the cost of borrowed funds accounted for as interest expense.

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Amount of interest expense incurred on a debt or other obligation to related party.

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

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Long-Term Debt and Revolving Promissory Note (Details 2) $ in Millions							12 Months Ended
	Sep. 15, 2016 USD ($)	Aug. 29, 2016 USD ($)	Aug. 22, 2016 USD ($)	Jan. 29, 2016 USD ($)	Sep. 21, 2015 USD ($)	Feb. 20, 2015 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	May 02, 2016 USD ($)	Oct. 13, 2015 USD ($)	Sep. 30, 2015 USD ($)	Jun. 15, 2015 USD ($)
Debt instruments
Net loss on early retirement of debt							$ 27	$ 0	$ 0
Long-term debt, gross							7,391
Amount of gross interest expense, net of capitalized interest and interest expense - affiliates
Gross interest expense							497	491	481
Capitalized interest							(19)	(18)	(17)
Total interest expense							478	473	464
Interest expense-affiliates, net							59	53	$ 40
Senior notes \| Qwest Corporation
Debt instruments
Long-term debt, gross							$ 7,259	7,229
Senior notes \| Qwest Corporation \| Minimum
Debt instruments
Interest rate, stated percentage (as a percent)							6.125%
Senior notes \| Qwest Corporation \| Maximum
Debt instruments
Interest rate, stated percentage (as a percent)							7.75%
Term loan \| Qwest Corporation
Debt instruments
Interest rate, stated percentage (as a percent)							2.52%
Long-term debt, gross							$ 100	100
6.5% Notes due 2056 \| Senior notes \| Qwest Corporation
Debt instruments
Face amount of debt instrument			$ 978
Interest rate, stated percentage (as a percent)			6.50%
Debt instrument face amount over-allotment			$ 128
Net proceeds from issuance of debt			$ 946
6.5% Notes due 2056 \| Senior notes \| Qwest Corporation \| Debt instrument, redemption period one
Debt instruments
Debt instrument redemption description			on or after September 1, 2021, at a redemption price equal to 100% of the principal amount redeemed
7.00% Notes due 2056 \| Senior notes \| Qwest Corporation
Debt instruments
Face amount of debt instrument				$ 235
Interest rate, stated percentage (as a percent)				7.00%
Net proceeds from issuance of debt				$ 227
7.00% Notes due 2056 \| Senior notes \| Qwest Corporation \| Debt instrument, redemption period one
Debt instruments
Debt instrument redemption description				on or after February 1, 2021, at a redemption price equal to 100% of the principal amount redeemed
6.625% Notes due 2055 \| Senior notes \| Qwest Corporation
Debt instruments
Face amount of debt instrument					$ 400
Interest rate, stated percentage (as a percent)					6.625%
Debt instrument face amount over-allotment												$ 10
Net proceeds from issuance of debt					$ 386
6.625% Notes due 2055 \| Senior notes \| Qwest Corporation \| Debt instrument, redemption period one
Debt instruments
Redemption price of debt instrument (as a percent)					100.00%
7.5% Notes due 2051 \| Senior notes \| Qwest Corporation
Debt instruments
Interest rate, stated percentage (as a percent)	7.50%
Repurchased face amount of Senior notes	$ 287
Net loss on early retirement of debt	$ 9
7.375% Notes Due 2051 \| Senior notes \| Qwest Corporation
Debt instruments
Interest rate, stated percentage (as a percent)		7.375%
Repurchased face amount of Senior notes		$ 661
Net loss on early retirement of debt		$ 18
8.375% Notes due 2016 \| Senior notes \| Qwest Corporation
Debt instruments
Interest rate, stated percentage (as a percent)										8.375%
Repurchased face amount of Senior notes										$ 235
7.200% Notes due 2026 \| Senior notes \| Qwest Corporation
Debt instruments
Interest rate, stated percentage (as a percent)											7.20%
Repurchased face amount of Senior notes											$ 250
6.875% Noted due 2033 \| Senior notes \| Qwest Corporation
Debt instruments
Interest rate, stated percentage (as a percent)											6.875%
Repurchased face amount of Senior notes											$ 150
7.625% Noted due 2015 \| Senior notes \| Qwest Corporation
Debt instruments
Interest rate, stated percentage (as a percent)													7.625%
Repurchased face amount of Senior notes													$ 92
Term Loan \| Term loan \| Qwest Corporation
Debt instruments
Face amount of debt instrument						$ 100
Long-term debt, gross							$ 100	$ 100
Term Loan covenant Debt to EBITDA Ratio							2.85
Term Loan \| Term loan \| Qwest Corporation \| Minimum \| London Interbank Offered Rate (LIBOR)
Debt instruments
Interest rate margin (as a percent)						1.50%
Term Loan \| Term loan \| Qwest Corporation \| Minimum \| Base Rate
Debt instruments
Interest rate margin (as a percent)						0.50%
Term Loan \| Term loan \| Qwest Corporation \| Maximum \| London Interbank Offered Rate (LIBOR)
Debt instruments
Interest rate margin (as a percent)						2.50%
Term Loan \| Term loan \| Qwest Corporation \| Maximum \| Base Rate
Debt instruments
Interest rate margin (as a percent)						1.50%