Condensed Consolidated Statements of Operations and Comprehensive Loss - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Income Statement [Abstract]
Revenue	$ 42,284	$ 42,612
Cost of goods sold	13,958	13,970
Gross profit	28,326	28,642
Operating expenses:
Research and development	5,499	5,530
Clinical and regulatory affairs	3,571	3,835
Marketing and sales	21,725	25,900
General and administrative	10,369	8,873
Restructuring costs	233	166
Total operating expenses	41,397	44,304
Loss from operations	(13,071)	(15,662)
Other income (expense):
Interest income	3	44
Interest expense	(5,807)	(4,295)
Other income (expense), net	363	(47)
Change in fair value of contingent consideration related to acquisition	1,100	(1,200)
Loss on debt extinguishment	(2,270)	0
Total other income (expense)	(6,611)	(5,498)
Net loss before income tax expense	(19,682)	(21,160)
Income tax expense	(85)	(154)
Net loss	(19,767)	(21,314)
Other comprehensive income (loss) foreign currency translation	(127)	356
Comprehensive loss	$ (19,894)	$ (20,958)
Basic and diluted net loss per share (in dollars per share)	$ (0.24)	$ (0.26)
Shares used in computing basic and diluted net loss per share (in shares)	83,706	82,928