Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Current assets:
Cash	$ 62,243	$ 87,176
Restricted cash, current portion	145	503
Accounts receivable, net of allowance of $628 in 2015 and $527 in 2014	5,273	5,942
Inventory	14,633	11,542
Prepaid expenses and other current assets	3,537	1,314
Total current assets	85,831	106,477
Property and equipment, net	15,047	14,574
Restricted cash, long term portion	1,428	808
Other assets	4,446	1,764
Total assets	106,752	123,623
Current liabilities:
Accounts payable	8,949	8,867
Accrued compensation	7,011	5,980
Other accrued liabilities	14,024	10,341
Deferred revenue	34	112
Equipment loan, current portion	2,340	2,340
Warrants	6,157	2,232
Total current liabilities	38,515	29,872
Equipment loan, long term portion	2,340	3,510
Senior secured term loan	23,086	20,964
Total long-term liabilities	25,426	24,474
Total liabilities	$ 63,941	$ 54,346
Commitments and contingencies (Note 5)
Convertible preferred stock	$ 240,585	$ 240,612
Stockholders’ deficit:
Common stock	1	1
Additional paid in capital	11,719	8,664
Notes receivable from officers		(192)
Accumulated deficit	(209,494)	(179,808)
Total stockholders’ deficit	(197,774)	(171,335)
Total liabilities, convertible preferred stock, and stockholders’ deficit	$ 106,752	$ 123,623