Consolidated Statements Of Comprehensive Income - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Statement of Comprehensive Income [Abstract]
Net income	$ 3,826	$ 6,399	$ 13,041	$ 16,100
Foreign currency:
Translation adjustment, net of taxes of $(29), $(38), $111 and $25	(90)	(88)	367	160
Distribution of WarnerMedia, net of taxes of $0, $0, $0 and $(38)	0	(12)	0	(182)
Securities:
Net unrealized gains (losses), net of taxes of $(12), $(15), $(8) and $(52)	(37)	(43)	(25)	(152)
Reclassification adjustment included in net income, net of taxes of $1, $1, $3 and $3	2	1	7	7
Derivative instruments:
Net unrealized gains (losses), net of taxes of $211, $(143), $213 and $(246)	843	(540)	867	(885)
Reclassification adjustment included in net income, net of taxes of $3, $3, $9 and $22	12	12	35	85
Distribution of WarnerMedia, net of taxes of $0, $0, $0 and $(12)	0	0	0	(24)
Defined benefit postretirement plans:
Net prior service credit arising during the period, net of taxes of $0, $583, $0 and $583	0	1,787	0	1,787
Amortization of net prior service credit included in net income, net of taxes of $(160), $(180), $(481) and $(484)	(490)	(551)	(1,472)	(1,477)
Distribution of WarnerMedia, net of taxes of $0, $0, $0 and $5	0	0	0	25
Other comprehensive income (loss)	240	566	(221)	(656)
Total comprehensive income	4,066	6,965	12,820	15,444
Less: Total comprehensive income attributable to noncontrolling interest	(331)	(373)	(829)	(1,107)
Total Comprehensive Income Attributable to AT&T	$ 3,735	$ 6,592	$ 11,991	$ 14,337