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

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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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Nominal or face amount used to calculate payment on derivative.

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- Definition

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

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- Definition

Number of interest rate derivative instruments held by the entity at the reporting date.

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

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Long-Term Debt and Credit Facilities - Additional Information (Details)		9 Months Ended
	Sep. 25, 2019 USD ($)	Sep. 30, 2019 USD ($)	Oct. 25, 2019 USD ($)	Oct. 24, 2019 USD ($)	Oct. 17, 2019 USD ($)	Oct. 15, 2019 USD ($)	Jun. 30, 2019 USD ($) derivative_agreement	Feb. 28, 2019 USD ($) derivative_agreement
Derivative [Line Items]
Repayments of debt		$ 1,100,000,000
Gain (loss) on extinguishment of debt		70,000,000
Subsequent Event
Derivative [Line Items]
Stated interest rate					5.75%
Repurchased face amount					$ 600,000,000
Interest Rate Swap \| Designated as Hedging Instrument
Derivative [Line Items]
Number of instruments \| derivative_agreement							6	5
Interest Rate Swap \| Designated as Hedging Instrument \| Cash Flow Hedging
Derivative [Line Items]
Notional amount							$ 1,500,000,000	$ 2,500,000,000
9.000% Centel Capital Corporation Notes \| Subsequent Event
Derivative [Line Items]
Stated interest rate						9.00%
Repurchased face amount						$ 148,000,000
Senior notes
Derivative [Line Items]
Repayments of debt		249,000,000
Senior notes \| 6.125% Senior Notes due 2021 \| Subsequent Event
Derivative [Line Items]
Stated interest rate			6.125%
Repurchased face amount			$ 240,000,000
Medium-term notes
Derivative [Line Items]
Repayments of debt		122,000,000
Level 3 Financing, Inc.
Derivative [Line Items]
Repayments of debt		400,000,000
Level 3 Financing, Inc. \| Senior notes \| 4.625% Senior Notes Due 2027
Derivative [Line Items]
Face amount	$ 1,000,000,000.0
Stated interest rate	4.625%
Level 3 Financing, Inc. \| Senior notes \| 6.125% Senior Notes due 2021
Derivative [Line Items]
Stated interest rate	6.125%
Repurchased face amount	$ 240,000,000
Level 3 Financing, Inc. \| Senior notes \| 5.75% Senior Notes Due 2022
Derivative [Line Items]
Stated interest rate	5.75%
Repurchased face amount	$ 600,000,000
Level 3 Financing, Inc. \| Senior notes \| 5.375% Senior Notes Due 2022
Derivative [Line Items]
Repayments of debt	160,000,000
Face amount	$ 1,000,000,000
Stated interest rate	5.375%
Level 3 Financing, Inc. \| Senior notes \| 5.375% Senior Notes Due 2022 \| Subsequent Event
Derivative [Line Items]
Face amount				$ 1,000,000,000
Stated interest rate			5.375%
Repurchased face amount			$ 160,000,000
Qwest Capital Funding, Inc.
Derivative [Line Items]
Repayments of debt		345,000,000
CenturyLink, Inc.
Derivative [Line Items]
Repayments of debt		$ 340,000,000