Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Consolidated Balance Sheets
Accounts receivable - trade, allowance (in dollars)	$ 1,355	$ 1,021
Common stock, par value (in dollars per share)	$ 1	$ 1
Common stock, shares issued	43,572,712us-gaap_CommonStockSharesIssued	43,479,186us-gaap_CommonStockSharesIssued
Common stock, shares outstanding	43,572,712us-gaap_CommonStockSharesOutstanding	43,479,186us-gaap_CommonStockSharesOutstanding

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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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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