Condensed Consolidated Statements of Operations and Comprehensive Loss (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Income Statement [Abstract]
Revenue	$ 33,264	$ 29,784
Cost of goods sold	8,969	7,256
Gross profit	24,295	22,528
Operating expenses:
Research and development	4,105	3,519
Clinical and regulatory affairs	2,200	2,364
Marketing and sales	16,143	15,249
General and administrative	7,163	5,885
Total operating expenses	29,611	27,017
Loss from operations	(5,316)	(4,489)
Other income (expense):
Interest income	59	10
Interest expense	(1,390)	0
Other income, net	358	684
Change in fair value of contingent consideration related to acquisition	11,800	(5,200)
Total other income (expense)	10,827	(4,506)
Net income (loss) before income tax expense	5,511	(8,995)
Income tax expense	(216)	(339)
Net income (loss)	5,295	(9,334)
Other comprehensive (loss) income (foreign currency translation)	(46)	328
Comprehensive income (loss)	$ 5,249	$ (9,006)
Basic net income (loss) per share (usd per share)	$ 0.08	$ (0.15)
Diluted net income (loss) per share (usd per share)	$ 0.08	$ (0.15)
Shares used in computing basic net income (loss) per share	63,405	62,189
Shares used in computing diluted net income (loss) per share	66,017	62,189