Condensed Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Income Statement [Abstract]
Revenue	$ 146,001	$ 132,475	$ 290,781	$ 265,112
Costs and operating expenses:
Cost of sales	73,235	69,377	145,830	130,578
Collaboration profit sharing	1,284	1,326	1,942	2,593
Research and development	33,592	28,092	63,506	52,078
Sales and marketing	29,874	28,078	58,669	54,014
General and administrative	15,418	16,352	30,473	31,994
Total costs and operating expenses	153,403	143,225	300,420	271,257
Loss from operations	(7,402)	(10,750)	(9,639)	(6,145)
Other income (expense):
Interest income	799	416	1,459	789
Interest expense	(3,812)	(3,646)	(7,577)	(7,250)
Foreign currency exchange gain (loss) and other, net	298	(1,496)	(230)	(2,440)
Other expense, net	(2,715)	(4,726)	(6,348)	(8,901)
Loss before income taxes	(10,117)	(15,476)	(15,987)	(15,046)
Provision for income taxes	(115)	(1,254)	(846)	(778)
Net loss	$ (10,232)	$ (16,730)	$ (16,833)	$ (15,824)
Basic net loss per share (in dollars per share)	$ (0.14)	$ (0.23)	$ (0.23)	$ (0.22)
Diluted net loss per share (in dollars per share)	$ (0.14)	$ (0.23)	$ (0.23)	$ (0.22)
Shares used in computing basic net loss per share (in shares)	72,921	71,861	72,754	71,563
Shares used in computing diluted net loss per share (in shares)	72,921	71,861	72,754	71,563