Discontinued Operations and Disposal Groups (Summary of Asset and Liabilities included in the Balance Sheet) (Details) - Discontinued Operations - Lumen's Mass Markets $ in Millions	Mar. 31, 2026 USD ($)
Assets
Current Assets	$ 132
Property, Plant, and Equipment - Net	3,544
Goodwill	392
Other Assets	204
Total Assets, discontinued operations	4,272
Liabilities [Abstract]
Current liabilities	185
Other liabilities	1
Total Liabilities, discontinued operations	$ 186

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