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

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1B
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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

Gross amount of debt extinguished.

+ References

No definition available.

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- Definition

The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
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Long-Term Debt and Credit Facilities - Term Loans and Certain Other Debt of Subsidiaries (Details) - USD ($) $ in Millions				12 Months Ended
	Oct. 26, 2020	Oct. 23, 2020	Nov. 27, 2019	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Qwest Corporation \| Senior Notes \| 6.625% Senior Notes
Long-term Debt and Credit Facilities
Amount of debt redeemed	$ 160
Stated interest rate	6.625%
Qwest Corporation \| Term Loan
Long-term Debt and Credit Facilities
Long-term debt, gross				$ 215	$ 215
Qwest Corporation \| Term Loan \| LIBOR
Long-term Debt and Credit Facilities
Basis spread (as a percent)				2.00%
Qwest Corporation \| CoBank ACB \| Variable Rate Term Loan
Long-term Debt and Credit Facilities
Proceeds from issuance of debt		$ 215
Qwest Corporation \| CoBank ACB \| Variable Rate Term Loan \| Minimum \| LIBOR
Long-term Debt and Credit Facilities
Basis spread (as a percent)		1.50%
Qwest Corporation \| CoBank ACB \| Variable Rate Term Loan \| Minimum \| Base Rate
Long-term Debt and Credit Facilities
Basis spread (as a percent)		0.50%
Qwest Corporation \| CoBank ACB \| Variable Rate Term Loan \| Maximum \| LIBOR
Long-term Debt and Credit Facilities
Basis spread (as a percent)		2.50%
Qwest Corporation \| CoBank ACB \| Variable Rate Term Loan \| Maximum \| Base Rate
Long-term Debt and Credit Facilities
Basis spread (as a percent)		1.50%
Qwest Corporation \| CoBank ACB \| Term Loan
Long-term Debt and Credit Facilities
Long-term debt, gross						$ 100
Level 3 Financing, Inc. \| Term Loan \| Tranche B 2027 Term Loan
Long-term Debt and Credit Facilities
Long-term debt, gross				$ 3,111	$ 3,111
Level 3 Financing, Inc. \| Term Loan \| Tranche B 2027 Term Loan \| Federal Funds Effective Rate
Long-term Debt and Credit Facilities
Basis spread (as a percent)			0.50%
Level 3 Financing, Inc. \| Term Loan \| Tranche B 2027 Term Loan \| LIBOR
Long-term Debt and Credit Facilities
Basis spread (as a percent)			1.00%	1.75%
Level 3 Financing, Inc. \| Term Loan \| Tranche B 2027 Term Loan \| Base Rate
Long-term Debt and Credit Facilities
Basis spread (as a percent)			0.75%
Level 3 Financing, Inc. \| Term Loan \| Tranche B 2027 Term Loan \| Eurodollar
Long-term Debt and Credit Facilities
Basis spread (as a percent)			1.75%