Segment Information (Tables)

9 Months Ended

Sep. 30, 2012

Segment Information

Schedule of total revenues from customers and collaboration partners by geographic region

	Three Months Ended				Nine Months Ended
	September 30,				September 30,
	2012		2011		2012		2011
	(in thousands)
United States	$	50,564	$	46,966	$	155,798	$	138,853
Outside of the United States	8,084		5,092		18,948		13,860
Total revenues	$	58,648	$	52,058	$	174,746	$	152,713