Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Mar. 31, 2012	Dec. 31, 2011
Trade accounts receivable, allowance for doubtful accounts	$ 201	$ 200
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	50,000,000	50,000,000
Common stock, issued	23,790,455	23,783,106
Common stock, outstanding	23,790,455	23,783,106
Preferred stock
Preferred stock, shares authorized	5,000,000	5,000,000
Series A Convertible Preferred stock
Preferred stock, par value	$ 0.01	$ 0.01
Preferred stock, liquidation preference value	$ 100	$ 100
Preferred stock, shares authorized	150,000	150,000
Preferred stock, issued
Preferred stock, outstanding