CONSOLIDATED BALANCE SHEET (Parenthetical) - USD ($) shares in Millions, $ in Millions	Jun. 30, 2019	Dec. 31, 2018
ASSETS
Allowance for trade and other receivables	$ 60	$ 94
Common Stock
EQUITY
Common Stock, par value (in dollars per share)	$ 0.01
Common Stock, shares issued (in shares)	4,011
Common Stock, Shares Authorized (in shares)	6,000
Class B Stock
EQUITY
Common Stock, par value (in dollars per share)	$ 0.01
Common Stock, shares issued (in shares)	71
Common Stock, Shares Authorized (in shares)	530

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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-Topic 310
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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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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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