Debt (Narrative) (Details) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024
Debt Instrument [Line Items]
Outstanding debt	$ 144,311	$ 131,835
Long-Term Debt, Weighted Average Interest Rate, at Point in Time	4.20%	4.20%
Outstanding commercial paper and other short-term borrowings	$ 0	$ 0
Debt Issued in Foreign Markets
Debt Instrument [Line Items]
Outstanding debt	$ 35,307	$ 30,685

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.

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+ Details

AT&T INC. 10-K