CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015
Cash Flows from Operating Activities:
Net loss	$ (8,922)	$ (4,073)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation	104	92
Provision to reduce inventory to net realizable value	26	334
Provision for sales returns	83	253
Share-based compensation	450	461
Amortization of debt discount and deferred debt issue costs	113	144
Amortization of bond premium in marketable securities	31	106
Amortization of intangible asset	155	155
(Gain) on sales of marketable securities	(2)	0
Loss on disposal of property, plant and equipment	2	20
Changes in assets and liabilities:
Accounts receivable, net	(86)	(171)
Accrued investment income	37	15
Inventories	(174)	(104)
Prepaid expenses and other current assets	9	(17)
Other current deferred assets	0	217
Other assets	175	(175)
Accounts payable	293	59
Accrued expenses	170	257
Deferred revenue	0	(353)
Accrued interest - current and long term	176	141
Other current liabilities	17	7
Net cash used in operating activities	(7,343)	(2,632)
Cash Flows from Investing Activities:
Purchases of marketable securities	0	(3,523)
Proceeds from sales and maturities of marketable securities	10,873	2,811
Proceeds from disposals of property, plant and equipment	0	14
Additions to property, plant and equipment	(72)	(211)
Net cash provided by (used in) investing activities	10,801	(909)
Cash Flows from Financing Activities:
Proceeds from distribution of restricted stock units	0	1
Proceeds from ATM offering	0	225
Proceeds from Registered Direct offering	0	7,636
Transaction costs from ATM offering	0	(8)
Transaction costs from Registered Direct offering	0	(603)
Principal payments on debt	(1,671)	(1,160)
Net cash (used in) provided by financing activities	(1,671)	6,091
Net increase in cash and cash equivalents	1,787	2,550
Cash and cash equivalents at beginning of year	2,485	774
Cash and cash equivalents at end of period	4,272	3,324
Cash paid during the year for:
Interest on term loan with Oxford Finance LLC	$ 407	$ 606