CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (USD $) In Thousands	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Deficit [Member]	Treasury Stock [Member]	Accumulated Other Comprehensive Income (Loss) [Member]
Balances at beginning of period at Dec. 31, 2008	$ 492,655	$ 423	$ 980,563	$ (365,431)	$ (124,852)	$ 1,952
Balances at beginning of period (in shares) at Dec. 31, 2008		42,339			(5,208)
Stock issued pursuant to employee stock plans	818		(942)	(10,875)	12,635
Stock issued pursuant to employee stock plans (in shares)					369
Stock-based compensation	13,394		13,394
Stock option purchase	(526)		(526)
Stock recovery for payment of withholding tax	(172)				(172)
Stock recovery for payment of withholding tax (in shares)					(14)
Net loss	(68,355)			(68,355)
Net change in unrealized gains (losses) on defined benefit plan and marketable securities	31					31
Translation adjustment	5,273					5,273
Other comprehensive loss	5,304
Comprehensive loss	(63,051)
Balances at end of period at Dec. 31, 2009	443,118	423	992,489	(444,661)	(112,389)	7,256
Balances at end of period (in shares) at Dec. 31, 2009		42,339			(4,853)
Stock issued pursuant to employee stock plans	853		(1,212)	(8,807)	10,872
Stock issued pursuant to employee stock plans (in shares)					370
Stock-based compensation	13,921		13,921
Issuance of common stock in connection with acquisitions	5,776			(4,832)	10,608
Issuance of common stock in connection with acquisitions (in shares)					327
Stock recovery for payment of withholding tax	(116)				(116)
Stock recovery for payment of withholding tax (in shares)					(8)
Net loss	(36,954)			(36,954)
Net change in unrealized gains (losses) on defined benefit plan and marketable securities	(85)					(85)
Translation adjustment	97					97
Other comprehensive loss	12
Comprehensive loss	(36,942)
Balances at end of period at Dec. 31, 2010	426,610	423	1,005,198	(495,254)	(91,025)	7,268
Balances at end of period (in shares) at Dec. 31, 2010	38,175	42,339			(4,164)
Stock issued pursuant to employee stock plans	2,160		(1,213)	(5,485)	8,858
Stock issued pursuant to employee stock plans (in shares)					440
Stock-based compensation	14,619		14,619
Stock recovery for payment of withholding tax	(134)				(134)
Stock recovery for payment of withholding tax (in shares)					(10)
Net loss	(23,791)			(23,791)
Net change in unrealized gains (losses) on defined benefit plan and marketable securities	449					449
Translation adjustment	(2,910)					(2,910)
Other comprehensive loss	(2,461)
Comprehensive loss	(26,252)
Balances at end of period at Dec. 31, 2011	$ 417,003	$ 423	$ 1,018,604	$ (524,530)	$ (82,301)	$ 4,807
Balances at end of period (in shares) at Dec. 31, 2011	38,605	42,339			(3,734)