Consolidated Balance Sheet (Parenthetical) - USD ($) shares in Thousands, $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Statement of Financial Position [Abstract]
Accounts Receivable, Allowance for Credit Loss, Current	$ 76	$ 73
Common Stock, Par Value Per Share	$ 1	$ 1
Common Stock, Shares, Outstanding	448,900	448,900
Treasury Stock, Shares	55,800	56,800

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

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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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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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