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

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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.

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- Definition

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

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- Definition

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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No definition available.

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- Definition

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

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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).

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- 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.

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- Definition

Weighted average interest rate of long-term debt outstanding.

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No definition available.

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- Definition

The amount for notes payable (written promise to pay), due to related parties.

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- Definition

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

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No definition available.

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- Definition

The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

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Long-Term Debt and Revolving Promissory Note Long-Term Debt and Revolving Promissory Note (Details 2) - USD ($) $ in Millions					9 Months Ended
	Oct. 13, 2015	Sep. 21, 2015	Jun. 15, 2015	Feb. 20, 2015	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
Long-term debt
Repayments of long-term debt					$ 112	$ 33
Senior notes
Long-term debt
Long-term debt, gross					7,629		$ 7,311
Medium-term loan
Long-term debt
Long-term debt, gross					100		0
Qwest Corporation \| Senior notes \| 6.625% Notes due 2055
Long-term debt
Interest rate (as a percent)		6.625%
Proceeds from debt, net of issuance costs		$ 386
Debt instrument face amount		$ 400			10
Qwest Corporation \| Senior notes \| 7.625% Notes due 2015
Long-term debt
Repayments of long-term debt			$ 92
Interest rate (as a percent)			7.625%
Qwest Corporation \| Medium-term loan \| Term loan
Long-term debt
Debt instrument face amount				$ 100
Long-term debt, gross					$ 100
Minimum \| Senior notes
Long-term debt
Interest rate (as a percent)					6.125%
Minimum \| Qwest Corporation \| Medium-term loan \| Term loan \| London Interbank Offered Rate (LIBOR)
Long-term debt
Basis spread on variable rate (as a percent)				1.50%
Minimum \| Qwest Corporation \| Medium-term loan \| Term loan \| Base Rate
Long-term debt
Basis spread on variable rate (as a percent)				0.50%
Maximum \| Senior notes
Long-term debt
Interest rate (as a percent)					8.375%
Maximum \| Qwest Corporation \| Medium-term loan \| Term loan \| London Interbank Offered Rate (LIBOR)
Long-term debt
Basis spread on variable rate (as a percent)				2.50%
Maximum \| Qwest Corporation \| Medium-term loan \| Term loan \| Base Rate
Long-term debt
Basis spread on variable rate (as a percent)				1.50%
CenturyLink, Inc. affiliate \| Loans payable \| Note payable - affiliate
Long-term debt
Note payable - affiliate					$ 827		$ 796
Weighted average interest rate (as a percent)					6.658%
CenturyLink, Inc. affiliate \| Qwest Corporation \| Loans payable \| Note payable - affiliate
Long-term debt
Maximum borrowing capacity					$ 1,000
Note payable - affiliate					$ 827
Weighted average interest rate (as a percent)					6.658%
Accrued interest payable on related party note payable					$ 18
Debt Instrument, Redemption, Period One \| Qwest Corporation \| Senior notes \| 6.625% Notes due 2055
Long-term debt
Debt instrument, redemption price, percentage		100.00%
Subsequent Event \| Qwest Corporation \| Senior notes \| 7.200% Notes due 2026
Long-term debt
Repayments of long-term debt	$ 250
Interest rate (as a percent)	7.20%
Subsequent Event \| Qwest Corporation \| Senior notes \| 6.875% Notes due 2033
Long-term debt
Repayments of long-term debt	$ 150
Interest rate (as a percent)	6.875%