Consolidated Statements of Income (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Revenues
Product sales	$ 150,117	$ 138,112
Collaborative research revenue	1,351	3,568
Royalty and license revenue	1,914	1,358
Total revenues	153,382	143,038
Operating expenses
Cost of product sales (excluding acquisition-related intangible amortization)	52,371	41,943
Acquisition-related intangible amortization	2,759	2,805
Research and development	28,586	28,963
Marketing and sales	19,045	16,522
General and administrative	18,954	18,153
Total operating expenses	121,715	108,386
Income from operations	31,667	34,652
Other income (expense)
Investment and interest income	2,538	735
Interest expense	(543)	(503)
Other income, net	128	177
Total other income, net	2,123	409
Income before income tax	33,790	35,061
Income tax expense	11,330	11,784
Net income	$ 22,460	$ 23,277
Net income per share
Basic	$ 0.50	$ 0.49
Diluted	$ 0.49	$ 0.48
Weighted average shares outstanding
Basic	45,124	47,861
Diluted	46,204	49,004