The value of the collateral (typically cash) that the entity receives in a financing transaction in exchange for securities lent. This item represents a liability in the financial statements of the lender of the securities.

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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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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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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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The total amount of the contingent obligation under letters of credit outstanding as of 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 - Additional Information (Details) - USD ($)		12 Months Ended
	Sep. 25, 2019	Dec. 31, 2019	Dec. 31, 2018	Nov. 29, 2019	Nov. 28, 2019	Aug. 25, 2019
Debt Instrument [Line Items]
Debt issuance costs, net		$ 34,000,000	$ 0
Tranche B 2024 Term Loan
Debt Instrument [Line Items]
Long-term debt, gross		$ 0	$ 4,611,000,000
Tranche B 2024 Term Loan \| LIBOR
Debt Instrument [Line Items]
Debt instrument, interest rate spread on debt			2.25%
5.750% Senior Notes due 2022
Debt Instrument [Line Items]
Debt instrument, stated interest rate		5.75%
Long-term debt, gross		$ 0	$ 600,000,000
Senior Notes
Debt Instrument [Line Items]
Long-term debt, gross		$ 5,515,000,000	5,315,000,000
Senior Notes \| CenturyLink, Inc.
Debt Instrument [Line Items]
Redemption price, percentage		101.00%
Senior Notes \| 3.400% Senior Notes Due 2027
Debt Instrument [Line Items]
Face amount				$ 750,000,000
Debt instrument, stated interest rate				3.40%
Senior Notes \| 3.875% Senior Secured Notes Due 2029
Debt Instrument [Line Items]
Face amount				$ 750,000,000
Debt instrument, stated interest rate				3.875%
Senior Notes \| Tranche B 2024 Term Loan
Debt Instrument [Line Items]
Face amount					$ 4,611,000,000
Repurchased face amount				$ 1,500,000,000
Senior Notes \| 4.625% Senior Notes Due 2027
Debt Instrument [Line Items]
Face amount	$ 1,000,000,000.0			$ 3,111,000,000
Debt instrument, stated interest rate	4.625%
Senior Notes \| 6.125% Senior Notes due 2021
Debt Instrument [Line Items]
Debt instrument, stated interest rate	6.125%					6.125%
Repurchased face amount	$ 240,000,000					$ 400,000,000
Senior Notes \| 5.750% Senior Notes due 2022
Debt Instrument [Line Items]
Debt instrument, stated interest rate	5.75%
Repurchased face amount	$ 600,000,000
Senior Notes \| 5.375% Senior Notes Due 2022
Debt Instrument [Line Items]
Face amount	$ 1,000,000,000
Debt instrument, stated interest rate	5.375%
Repayments of debt	$ 160,000,000
Term Loan \| Tranche B 2027 Term Loan
Debt Instrument [Line Items]
Long-term debt, gross		$ 3,111,000,000	0
Term Loan \| Tranche B 2027 Term Loan \| Fed Funds Effective Rate Overnight Index Swap Rate
Debt Instrument [Line Items]
Debt instrument, interest rate spread on debt		50.00%
Term Loan \| Tranche B 2027 Term Loan \| LIBOR
Debt Instrument [Line Items]
Debt instrument, interest rate spread on debt		100.00%
Term Loan \| Tranche B 2027 Term Loan \| Base Rate
Debt Instrument [Line Items]
Debt instrument, stated interest rate		0.75%
Term Loan \| Tranche B 2027 Term Loan \| Eurodollar
Debt Instrument [Line Items]
Debt instrument, interest rate spread on debt		1.75%
Letter of Credit \| Letter of Credit
Debt Instrument [Line Items]
Letters of credit outstanding, amount		$ 23,000,000	30,000,000
Letter of Credit \| Collateralized Debt Obligations \| Letter of Credit
Debt Instrument [Line Items]
Collateralized financings		$ 18,000,000	$ 24,000,000