Divestiture - Additional Information (Details) $ in Millions	3 Months Ended
Mar. 31, 2026 USD ($) state	Feb. 02, 2026 USD ($) state
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of states in which entity operates \| state	14
Lumen Technologies, Inc.
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
IRU term	20 years
Lumen Mass Markets fiber-to-the-home business
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Additional depreciation if disposal group did not meet the held for sale criteria	$ 9
Lumen Mass Markets fiber-to-the-home business \| Disposed of by Sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of states in which entity operates \| state		11
Consideration		$ 5,720
Net pre-tax loss on disposal	$ 242
Contractual credits and commercial agreements liabilities		517
Potential future cost obligations		18
Net assets		2,600
Property, plant and equipment, net		1,500
Goodwill		1,100
Other net assets		40
Mass Markets fiber-to-the home business \| Disposed of by Sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Consideration		2,880
Commercial agreements		399
Contractual credits		$ 118

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Indefeasible Right to Use (IRU), Contract Term

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

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Amount before tax of gain (loss) recognized on the sale or disposal of a disposal group. Excludes discontinued operations.

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