Consolidated Balance Sheet (Parenthetical) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Consolidated Balance Sheet
Allowances for doubtful accounts receivable	$ 95	$ 103
Common stock, par value per share (in dollars per share)	$ 0.01	$ 0.01
Common stock, Shares outstanding (in shares)	576,575,168	594,884,237

A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible.

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Face amount or stated value per share of common stock.

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

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