Consolidated Balance Sheet (Parenthetical) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Consolidated Balance Sheet
Allowances for doubtful accounts receivable	$ 172	$ 161
Common stock, par value per share (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares issued (in shares)	944,033,056	944,033,056
Common stock, Shares outstanding (in shares)	575,196,371	575,184,835
Treasury stock (in shares)	368,836,685	368,848,221

Amount of allowance for credit loss on accounts receivable, classified as current.

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