Condensed Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Per Share data	Sep. 30, 2011	Dec. 31, 2010
Condensed Consolidated Balance Sheets
Trade accounts receivable, allowances (in dollars)	$ 15,502	$ 13,772
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, authorized shares	125,000	125,000
Common stock, issued shares	38,606	38,581
Common stock, outstanding shares	38,606	38,581

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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