CONSOLIDATED BALANCE SHEETS (Parenthetical) $ in Thousands	Dec. 31, 2018 USD ($) shares	Dec. 31, 2018 ₪ / shares	Dec. 31, 2017 USD ($) shares	Dec. 31, 2017 ₪ / shares
Allowance for doubtful accounts receivable (in dollars) \| $	$ 790		$ 790
Ordinary shares, par value (in NIS per share) \| ₪ / shares		₪ 0.01		₪ 0.01
Ordinary shares, shares authorized	100,000,000		100,000,000
Ordinary shares, shares issued	58,002,942		56,558,952
Ordinary shares, shares outstanding	29,091,176		29,443,000
Treasury stock, shares	28,911,766		27,115,952

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

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