CONDENSED CONSOLIDATED BALANCE SHEET (Parenthetical) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Statement of Financial Position [Abstract]
Allowance for doubtful accounts	$ 66	$ 97
Common stock - par value (in usd per share)	$ 0.001	$ 0.001
Common stock - shares authorized (in shares)	3,580,000,000	3,580,000,000
Common stock - shares outstanding (in shares)	633,000,000	684,000,000
Treasury stock - shares (in shares)	1,081,000,000	1,021,000,000

Amount of allowance for credit loss on accounts receivable.

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Face amount or stated value per share of common stock.

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Number of common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends.

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