Condensed Consolidated Balance Sheets (Parentheticals) - USD ($) $ in Millions	Mar. 31, 2018	Dec. 31, 2017
Cash and Cash Equivalents
Restricted Cash and Cash Equivalents, Current	$ 18	$ 18
Accounts Receivable
net allowance for doubtful accounts	$ 19	$ 19
Common Stock
par value	$ 0.01	$ 0.01
shares authorized	300,000,000	300,000,000
shares issued	170,605,906	170,605,906
shares outstanding	82,556,847	82,556,847
Treasury stock, shares	88,049,059	88,049,059

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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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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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Amount of cash and cash equivalents restricted as to withdrawal or usage, classified as current. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Number of shares issued which are neither cancelled nor held in the treasury.

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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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