Condensed Consolidated Statements of Operations and Comprehensive Loss - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Income Statement [Abstract]
Revenue	$ 38,231	$ 37,150	$ 114,380	$ 108,741
Cost of goods sold	11,195	13,573	36,306	32,362
Gross profit	27,036	23,577	78,074	76,379
Operating expenses:
Research and development	5,459	5,313	17,683	13,876
Clinical and regulatory affairs	3,956	2,482	11,003	7,404
Marketing and sales	19,662	18,438	59,103	53,748
General and administrative	7,293	6,271	21,432	19,366
Total operating expenses	36,370	32,504	109,221	94,394
Loss from operations	(9,334)	(8,927)	(31,147)	(18,015)
Other income (expense):
Interest income	34	63	116	189
Interest expense	(1,506)	(1,422)	(4,460)	(4,261)
Other income (expense), net	(89)	(4,198)	735	(3,987)
Change in fair value of contingent consideration related to acquisition	0	200	(200)	8,228
Total other income (expense)	(1,561)	(5,357)	(3,809)	169
Net loss before income tax (expense) benefit	(10,895)	(14,284)	(34,956)	(17,846)
Income tax (expense) benefit	(22)	346	(175)	210
Net loss	(10,917)	(13,938)	(35,131)	(17,636)
Other comprehensive income (loss) foreign currency translation	463	2,704	(1,207)	2,727
Comprehensive loss	$ (10,454)	$ (11,234)	$ (36,338)	$ (14,909)
Basic and diluted net loss per share	$ (0.16)	$ (0.21)	$ (0.52)	$ (0.28)
Shares used in computing basic and diluted net loss per share	67,810	65,494	67,568	63,444