Disposal Group, Including Discontinued Operation, Transaction Expenses

No definition available.

Name:	lumn_DisposalGroupIncludingDiscontinuedOperationTransactionExpenses
Namespace Prefix:	lumn_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of consideration received or receivable for the disposal of assets and liabilities, including discontinued operation.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount classified as liabilities attributable to disposal group held for sale or disposed of.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
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Balance Type:	credit
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- Definition

The number of states the entity operates in as of the balance sheet date.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Amount of stock repurchase plan authorized.

+ References

No definition available.

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Period which shares may be purchased under a stock repurchase plan authorized by an entity's Board of Directors, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

+ References

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Balance Type:	na
Period Type:	duration

- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

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- Details

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Namespace Prefix:
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Balance Type:
Period Type:

- Details

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- Details

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Subsequent Events (Details) - Subsequent Event	Aug. 04, 2021 shares	Aug. 03, 2021 USD ($) state	Jul. 25, 2021 USD ($)
Subsequent Event [Line Items]
Repurchase program, period		24 months
Repurchase program, authorized amount		$ 1,000,000,000.0
Number of shares repurchased \| shares	0
Latin American Business \| Level 3 Parent, LLC \| Discontinued Operations, Disposed of by Sale
Subsequent Event [Line Items]
Cash consideration from disposal of business			$ 2,735,000,000
Local Exchange Business in Midwestern and Southern States \| Discontinued Operations, Disposed of by Sale
Subsequent Event [Line Items]
Cash consideration from disposal of business		$ 7,500,000,000
Number of states in which the business is conducted \| state		20
Assumed indebtedness from disposal of business		$ 1,400,000,000
Purchaser's transaction expenses		$ 245,000,000