Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Current Assets
Cash and cash equivalents	$ 76,583	$ 117,185
Investments	26,939	0
Accounts receivable, net	13,535	14,867
Inventories	11,919	11,520
Prepaid expenses and other current assets	1,899	2,451
Total current assets	130,875	146,023
Property and equipment, net	13,592	10,966
Other Assets
Restricted cash	600	600
Intangible assets, net	932	995
Goodwill	753	753
Other long-term assets	29	32
Total assets	146,781	159,369
Current liabilities
Accounts payable	5,728	4,718
Accrued expenses	7,495	7,811
Deferred revenue	305	305
Current portion of long-term debt	301	295
Total current liabilities	13,829	13,129
Other long-term liabilities	200	220
Deferred revenue	4,549	4,625
Long-term debt	105	183
Total liabilities	18,683	18,157
Commitments and contingencies	0	0
Stockholders' equity
Preferred stock, $0.00001 par value:	0	0
Common stock, $0.00001 par value:	0	0
Additional paid-in capital	468,844	467,075
Accumulated deficit	(340,376)	(325,342)
Accumulated other comprehensive loss	(370)	(521)
Total stockholders’ equity	128,098	141,212
Total liabilities and stockholders’ equity	$ 146,781	$ 159,369