Condensed Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands	Jun. 30, 2011	Dec. 31, 2010
Condensed Consolidated Balance Sheets
Trade accounts receivable, allowance	$ 1,357	$ 1,159
Preferred stock, shares authorized	1,000	1,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, shares authorized	70,000	70,000
Common stock, shares issued	37,535	37,250
Common stock, shares outstanding	37,535	37,250