Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
Consolidated Balance Sheets
Accounts receivable, allowances (in dollars)	$ 1,422	$ 7,367
Property and equipment, accumulated depreciation (in dollars)	$ 64,929	$ 58,159
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized	1,000	1,000
Preferred stock, shares issued	0	0
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized	100,000	100,000
Common stock, shares issued	74,487	74,487
Treasury stock, shares	1,919	4,363