CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Current assets
Cash and cash equivalents	$ 2,743	$ 8,766
Short-term investments		1,002
Accounts receivable, net	522	559
Inventories	1,048	1,451
Prepaid expenses and other	1,124	473
Total current assets	5,437	12,251
Property and equipment, net	885	1,274
Goodwill	13,276	13,276
Intangible assets, net	167	223
Other	123	121
Total assets	19,888	27,145
Current liabilities
Accounts payable	165	561
Deferred revenue	1,273	271
Accrued expenses and other	2,094	2,502
Total current liabilities	3,532	3,334
Convertible notes payable	8,702	8,250
Other long-term liabilities	391	233
Total liabilities	12,625	11,817
Commitments and contingencies (Note 4)
Stockholders' equity
Preferred stock, $0.01 par value; 20,000 shares authorized; none issued and outstanding
Common stock, $0.001 par value; 120,000 shares authorized; 6,677 shares and 6,630 shares issued and outstanding at June 30, 2017 and December 31, 2016 respectively	7	7
Additional paid-in capital	229,675	229,341
Accumulated deficit	(222,419)	(214,020)
Total stockholders' equity	7,263	15,328
Total liabilities and stockholders' equity	$ 19,888	$ 27,145

Carrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer), for goods or services (including trade receivables) that have been delivered or sold in the normal course of business, reduced to the estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.