UNAUDITED CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) (USD $) In Thousands, except Share data	Sep. 30, 2011	Dec. 31, 2010
Accounts receivable, allowance for doubtful accounts	$ 824	$ 1,990
Fixed assets, accumulated depreciation	$ 106,732	$ 94,432
Preferred shares, issued	0	0
Class A Shares
Common stock, no par value	$ 0	$ 0
Common stock, shares issued	29,144,233	28,758,734
Class B Shares
Common stock, no par value	$ 0	$ 0
Common stock, shares issued	2,503	2,503
Common stock, shares outstanding	2,503	2,503