Balance Sheets (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Statement of Financial Position [Abstract]
Customer receivables, allowances	$ 9,069	$ 8,067
Common stock, par value	$ 0.10	$ 0.10
Common stock, shares authorized	140,000,000us-gaap_CommonStockSharesAuthorized	140,000,000us-gaap_CommonStockSharesAuthorized
Common stock, shares outstanding	86,094,297us-gaap_CommonStockSharesOutstanding	86,164,917us-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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The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

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