CONDENSED CONSOLIDATED BALANCE SHEET (Parenthetical) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Statement of Financial Position [Abstract]
Allowance for doubtful accounts	$ 127	$ 100
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)	701,000,000	796,000,000
Treasury stock - shares (in shares)	995,000,000	897,000,000

For an unclassified balance sheet, a valuation allowance for receivables due a company that are expected to be uncollectible.

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Face amount or stated value per share of common stock.

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The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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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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