Consolidated Balance Sheet Details - Accrued Expenses (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Balance Sheet Related Disclosures [Abstract]
Accrued product returns	$ 99	$ 1,985
Accrued interest payable, current	121	178
Accrued clinical trial costs	3,657	1,162
Other accrued expenses	2,497	1,292
Accrued expenses	$ 6,374	$ 4,617