Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
CURRENT ASSETS:
Cash and cash equivalents	$ 45,741	$ 98,044
Short-term investments	46,593	0
Accounts receivable, net of allowance for doubtful accounts of $15 and $106 as of December 31, 2015 and December 31, 2014, respectively	22,824	24,695
Inventories	10,775	8,360
Prepaid expenses and other current assets	4,129	2,610
Deferred cost of goods sold	757	1,001
Total current assets	130,819	134,710
Property and equipment, net	9,156	8,862
Goodwill	513	513
Other assets	426	169
Total assets	140,914	144,254
CURRENT LIABILITIES:
Accounts payable	15,140	10,154
Accrued liabilities	11,856	9,181
Debt, current	0	12,451
Deferred revenue, current	27,893	22,014
Total current liabilities	54,889	53,800
Debt, non-current	20,000	7,301
Deferred revenue, non-current	31,369	24,141
Other liabilities	463	857
Total liabilities	$ 106,721	$ 86,099
Commitments and contingencies (Note 6)
Stockholders’ equity:
Preferred stock, par value of $0.001 per share - 25,000,000 shares authorized as of December 31, 2015 and December 31, 2014; no shares issued and outstanding as of December 31, 2015 and December 31, 2014	$ 0	$ 0
Common stock, par value of $0.001 per share - 500,000,000 shares authorized as of December 31, 2015 and December 31, 2014; 49,017,293 and 46,028,908 shares issued and outstanding as of December 31, 2015 and December 31, 2014, respectively	49	46
Additional paid–in capital	231,289	208,998
Accumulated other comprehensive loss	(61)	0
Accumulated deficit	(197,084)	(150,889)
Total stockholders’ equity	34,193	58,155
Total liabilities and stockholders’ equity	$ 140,914	$ 144,254