Divestiture - Additional Information (Details) $ in Millions	3 Months Ended
Mar. 31, 2026 USD ($)	Feb. 02, 2026 USD ($) state
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
IRU term	20 years
Mass Markets Fiber-to-the Home Business
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Additional depreciation and amortization if held for sale criteria is not met	$ 15
Disposed of by sale \| Mass Markets Fiber-to-the Home Business
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of states in which the business is conducted \| state		11
Cash consideration of planned divestiture		$ 5,720
Pre-tax gain on the disposal	$ 596
Contractual credits and commercial agreements liabilities		729
Commercial agreements		497
Contractual credits		232
Potential future cost obligations		36
Net assets		4,300
Property, plant and equipment, accumulated depreciation		2,800
Goodwill		1,300
Other net assets		$ 162

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

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