Revenue Recognition - Contract Costs (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2024	Mar. 31, 2023
Acquisition Costs
Capitalized Contract Cost [Line Items]
Beginning Balance	$ 58	$ 61
Cost incurred	10	9
Amortization	(11)	(12)
Ending Balances	57	58
Fulfillment Costs
Capitalized Contract Cost [Line Items]
Beginning Balance	46	46
Cost incurred	10	10
Amortization	(9)	(10)
Ending Balances	$ 47	$ 46

Capitalized Contract Cost, Incurred

No definition available.

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Namespace Prefix:	lumn_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of amortization expense for asset recognized from cost incurred to obtain or fulfill contract with customer.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 340
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479483/340-40-50-3

+ Details

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Balance Type:	debit
Period Type:	duration

- 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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 340
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479483/340-40-50-3

+ Details

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- Definition

Amount, after accumulated amortization and accumulated impairment loss, of asset recognized from cost incurred to obtain or fulfill contract with customer.

+ References

+ Details

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- Details

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- Details

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