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, allowance for doubtful accounts	$ 3,819	$ 2,527
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares issued	88,756	91,594
Common stock, shares outstanding	88,756	91,594

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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