Consolidated Balance Sheets Parenthetical (USD $) In Thousands, except Share data, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
Current Assets:
Allowance for doubtful accounts	$ 434	$ 1,090
Stockholders' Equity:
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	75,000,000	75,000,000
Common stock, shares issued and outstanding	64,015,789	63,652,228
Preferred Stock [Member]
Stockholders' Equity:
Preferred stock, shares authorized	20,000,000	20,000,000
Preferred Stock Series A Junior Participating [Member]
Stockholders' Equity:
Preferred stock, shares authorized	75,000	75,000