CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Balance Sheet Parenthetical Disclosures
Accounts receivable, allowance (in dollars)	$ 4,755	$ 4,425
Common stock, par value (in dollars per share)	$ 1.00	$ 1.00
Common stock, shares authorized	750,000,000	750,000,000
Common stock, shares issued	469,829,639	469,435,678
Common stock, shares outstanding	469,829,639	469,435,678

The valuation allowance as of the balance sheet date to reduce the gross amount of receivables to estimated net realizable value, which would be presented in parentheses on the face of the balance sheet.

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Face amount or stated value per share of common stock.

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