Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
Consolidated Balance Sheets [Abstract]
Allowance for doubtful accounts	$ 1,500	$ 1,700
Common stock, par value
Common stock, shares authorized	40,000,000	40,000,000
Common stock, shares issued	24,576,000	24,235,000
Common stock, shares outstanding	24,576,000	24,235,000