Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Earnings Per Share
Net income	$ 4,348	$ 4,759
Less: Net income attributable to noncontrolling interest	(252)	(97)
Net Income attributable to AT&T	4,096	4,662
Share-based payment	6	5
Numerator for diluted earnings per share	$ 4,102	$ 4,667
Weighted average number of common shares outstanding	7,313	6,161
Share-based payment (in shares)	29	19
Denominator for diluted earnings per share	7,342	6,180
Basic Earnings Per Share Attributable to AT&T	$ 0.56	$ 0.75
Diluted Earnings Per Share Attributable to AT&T	$ 0.56	$ 0.75

Amount of increase (decrease) to net income used for calculating diluted earnings per share (EPS), resulting from the assumed exercise stock options, restrictive stock units (RSUs), convertible preferred stock of an employee stock ownership plan (ESOP), and other dilutive convertible securities.

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