Balance Sheet Details - Other (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Accounts Receivable, Net
Accounts receivable	$ 17,568	$ 14,800
Less allowance for doubtful accounts	(620)	(495)
Accounts receivable, net	16,948	14,305
Inventory
Finished goods	3,518	2,014
Work in process	2,459	2,105
Raw materials	2,989	2,725
Total inventory	8,966	6,844
Accrued Liabilities
Accrued contract payments (see Note 8)	1,000	823
Accrued sales commissions	2,065	1,641
Accrued clinical study payments	643	1,167
Accrued bonuses	4,565	6,122
Accrued vacation benefits	2,033	1,382
Accrued Employee Stock Purchase Plan deductions	865	4
Other accrued liabilities	4,986	2,772
Total accrued liabilities	$ 16,157	$ 13,911