CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (USD $) In Thousands	Total	Class A	Class B	Treasury Stock	Additional Paid-In Capital	Accumulated Other Comprehensive Income (Loss)	Accumulated Deficit
Beginning Balance at Dec. 31, 2008	$ 179,926	$ 4	$ 3	$ (185)	$ 366,798	$ (2,055)	$ (184,639)
Beginning Balance (in shares) at Dec. 31, 2008		36,627	27,141
Class A common shares issued upon exercise of employee stock-based awards and purchases made under the employee purchase plan (in shares)		267
Class A common shares issued upon exercise of employee stock-based awards and purchases made under the employee purchase plan	77				77
Net cash paid for payroll taxes on restricted stock unit releases	(275)				(275)
Stock-based compensation expense	10,696				10,696
Recognition of previously unrecognized tax benefits	2,744				2,744
Cumulative translation adjustment	2,006					2,006
Temporary gain on investment in auction rate securities, net of tax	207					207
Net income (loss)	(2,688)						(2,688)
Ending Balance at Dec. 31, 2009	192,693	4	3	(185)	380,040	158	(187,327)
Ending Balance (in shares) at Dec. 31, 2009		36,894	27,141
Conversion of Class B shares to Class A shares (in shares)		6,180	(6,180)
Conversion of Class B shares to Class A shares		1	(1)
Class A common shares issued upon exercise of employee stock-based awards and purchases made under the employee purchase plan (in shares)		709
Class A common shares issued upon exercise of employee stock-based awards and purchases made under the employee purchase plan	1,883				1,883
Net cash paid for payroll taxes on restricted stock unit releases	(262)				(262)
Stock-based compensation expense	6,172				6,172
Cumulative translation adjustment	251					251
Temporary gain on investment in auction rate securities, net of tax	(117)					(117)
Net income (loss)	4,945						4,945
Ending Balance at Dec. 31, 2010	205,565	5	2	(185)	387,833	292	(182,382)
Ending Balance (in shares) at Dec. 31, 2010		43,783	20,961
Conversion of Class B shares to Class A shares (in shares)		9,848	(9,848)
Conversion of Class B shares to Class A shares		1	(1)
Class A common shares issued upon exercise of employee stock-based awards and purchases made under the employee purchase plan (in shares)		1,292
Class A common shares issued upon exercise of employee stock-based awards and purchases made under the employee purchase plan	3,029				3,029
Net cash paid for payroll taxes on restricted stock unit releases	(797)				(797)
Stock-based compensation expense	5,562				5,562
Cumulative translation adjustment	(517)					(517)
Net income (loss)	19,902						19,902
Ending Balance at Dec. 31, 2011	$ 232,744	$ 6	$ 1	$ (185)	$ 395,627	$ (225)	$ (162,480)
Ending Balance (in shares) at Dec. 31, 2011		54,923	11,113