Condensed Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Share data	Sep. 30, 2011	Dec. 31, 2010
Condensed Consolidated Balance Sheets
Accounts and other receivables, allowances for doubtful accounts	$ 25	$ 97
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	100,000,000	100,000,000
Common stock, shares issued	31,760,085	31,016,812
Common stock, shares outstanding	28,940,662	28,228,603
Treasury stock, shares	2,819,423	2,788,209