Consolidated Statement Of Changes In Stockholders' Equity - 6 months ended Jun. 30, 2017 - USD ($) shares in Millions, $ in Millions	Total	Common Stock [Member]	Additional Paid-In Capital [Member]	Retained Earnings [Member]	Treasury Stock [Member]	Accumulated Other Comprehensive Income Attributable to AT&T, net of tax [Member]	Noncontrolling Interest [Member]
Balance at beginning of year at Dec. 31, 2016	$ 124,110	$ 6,495	$ 89,604	$ 34,734	$ (12,659)	$ 4,961	$ 975
Balance at beginning of year (in shares) at Dec. 31, 2016		6,495			(356)
Issuance of stock		$ 0
Issuance of stock (in shares)		0
Repurchase and acquisition of common stock					$ (504)
Repurchase and acquisition of common stock (in shares)					(13)
Issuance of treasury stock			4		$ 466
Issuance of treasury stock, (in shares)					14
Share-based payments			(137)
Net income attributable to AT&T ($1.19 per diluted share)	7,384			7,384
Dividends to stockholders ($0.98 per share)				(6,053)
Other				2
Other comprehensive income attributable to AT&T	428					428
Net income attributable to noncontrolling interest	204						204
Distributions							(174)
Acquisitions of noncontrolling interests							132
Translation adjustments attributable to noncontrolling interest, net of taxes	(4)						(4)
Balance at end of period at Jun. 30, 2017	$ 125,858	$ 6,495	$ 89,471	$ 36,067	$ (12,697)	$ 5,389	$ 1,133
Balance at end of period (in shares) at Jun. 30, 2017		6,495			(355)