Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Consolidated Balance Sheets
Receivables: allowance for doubtful accounts (in dollars)	$ 697	$ 668
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized	68,000,000us-gaap_CommonStockSharesAuthorized	68,000,000us-gaap_CommonStockSharesAuthorized
Common stock, shares outstanding	47,806,190us-gaap_CommonStockSharesOutstanding	47,740,957us-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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Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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