Condensed Consolidated Statements of Operations (Unaudited) (USD $) In Thousands, except Per Share data	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Condensed Consolidated Statements of Operations [Abstract]
NET REVENUES	$ 64,244	$ 80,626	$ 200,248	$ 221,729
COST OF REVENUES	28,567	33,937	86,797	95,132
GROSS PROFIT	35,677	46,689	113,451	126,597
OPERATING EXPENSES:
Research and development	12,637	11,681	37,389	34,594
Selling, general and administrative	10,985	12,770	34,748	35,738
Total operating expenses	23,622	24,451	72,137	70,332
INCOME FROM OPERATIONS	12,055	22,238	41,314	56,265
OTHER INCOME (EXPENSE):
Interest income	186	146	553	416
Interest expense		(49)	(18)	(191)
Other income, net	66	40	141	115
Total other income, net	252	137	676	340
INCOME BEFORE INCOME TAXES	12,307	22,375	41,990	56,605
PROVISION FOR INCOME TAXES	3,095	7,455	12,992	19,618
NET INCOME	$ 9,212	$ 14,920	$ 28,998	$ 36,987
NET INCOME PER SHARE:
Basic	$ 0.15	$ 0.24	$ 0.47	$ 0.59
Diluted	$ 0.15	$ 0.24	$ 0.46	$ 0.59
CASH DIVIDENDS PER COMMON SHARE	$ 0.040	$ 0.035	$ 0.110	$ 0.105
WEIGHTED AVERAGE SHARES USED IN COMPUTING PER SHARE AMOUNTS:
Basic	62,043	61,936	62,017	62,236
Diluted	62,465	62,311	62,850	62,633