Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Cash flows from operating activities:
Net loss	$ (25,650)	$ (31,554)	$ (12,687)
Adjustments to reconcile net loss to net cash used in operating activities:
Loss on extinguishment of debt	0	0	5,617
Gain on sale of Agera	0	0	(467)
Stock issued for exclusive channel collaboration agreement	5,154	6,406	6,917
Stock-based compensation expense	1,239	1,150	1,224
Warrant revaluation and other finance (income) expense	(3,930)	1,053	(20,404)
Derivative revaluation expense	0	0	23
Deferred tax benefit	0	0	(2,500)
Loss on disposal of property and equipment	13	5	0
Depreciation and amortization	883	863	821
Provision for doubtful accounts	12	(20)	25
Amortization of debt issuance costs	0	0	146
Change in operating assets and liabilities:
Accounts receivable	12	54	(60)
Inventory	26	(120)	(477)
Prepaid expenses	(76)	69	(196)
Other assets	214	(215)	0
Accounts payable	(1,834)	2,037	(966)
Accrued expenses and other liabilities	1,373	188	407
Deferred revenue	268	9	83
Miscellaneous other	0	0	(81)
Net cash used in operating activities	(22,296)	(20,075)	(22,575)
Cash flows from investing activities:
Purchase of property and equipment	(242)	(360)	(493)
Proceeds from the sale of Agera	0	0	1,002
Net cash (used in) provided by investing activities	(242)	(360)	509
Cash flows from financing activities:
Debt issuance costs	0	0	(46)
Net proceeds from preferred stock	0	0	7,864
Net proceeds from common stock	0	47,118	40,185
Subscription received	0	2,004	0
Payments on insurance loan	0	0	(97)
Principal payments on note payable	0	0	(4,823)
Dividends paid on preferred stock	0	0	(470)
Net cash provided by financing activities	0	49,122	42,613
Net (decrease) increase in cash and cash equivalents	(22,538)	28,687	20,547
Cash and cash equivalents, beginning of period	60,033	31,346	10,799
Cash and cash equivalents, end of period	$ 37,495	$ 60,033	$ 31,346