Segment Information (Reconciliation Of Operating Income Loss to Consolidated Statement Of Income) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
AT&T Operating Income	$ 6,002	$ 5,537
Interest expense	1,708	1,626
Equity in net income of affiliates	538	521
Other income (expense) — net	935	2,157
Income from Continuing Operations Before Income Taxes	5,767	6,589
Operating Segments
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
AT&T Operating Income	6,713	6,385
Operating Segments \| Communications
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
AT&T Operating Income	6,743	6,487
Operating Segments \| Latin America
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
AT&T Operating Income	(30)	(102)
Corporate
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
AT&T Operating Income	(738)	(630)
Reconciling Items
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Transaction and other costs	0	(98)
Amortization of intangibles acquired	(17)	(27)
Benefit-related gains (losses)	$ 44	$ (93)

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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