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Contractual interest rate for funds borrowed, under the debt agreement.

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Fair value portion of warrants not settleable in cash classified as equity.

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Secured Promissory Note Payable to Oxford Finance (Details) - USD ($)			3 Months Ended		6 Months Ended
	Feb. 13, 2018	Dec. 22, 2016	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Secured Promissory Note Payable to Oxford Finance (Details) [Line Items]
Debt Instrument, Interest Rate, Stated Percentage			8.00%		8.00%
Interest Paid, Including Capitalized Interest, Operating and Investing Activities					$ 189,000	$ 148,000
Debt Conversion, Converted Instrument, Amount	$ 14,200,000
Loan Agreement [Member] \| Oxford Finance [Member]
Secured Promissory Note Payable to Oxford Finance (Details) [Line Items]
Long-term Debt, Gross		$ 5,000,000
Debt Instrument, Payment Terms		secured promissory note and is repayable over four years, with interest only payable over the first 12 months and the balance fully amortized over the subsequent 36 months
Debt Instrument, Periodic Payment Terms, Balloon Payment to be Paid			$ 325,000		325,000
Interest Expense, Debt			122,000	$ 129,000	252,000	255,000
Interest Paid, Including Capitalized Interest, Operating and Investing Activities			$ 94,000	$ 91,000	189,000	$ 148,000
Debt Conversion, Converted Instrument, Amount					$ 250,000
Convertible Preferred Stock [Member] \| Series C Preferred Stock [Member] \| Loan Agreement [Member] \| Oxford Finance [Member]
Secured Promissory Note Payable to Oxford Finance (Details) [Line Items]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in Shares)			7,563		7,563
Class of Warrant or Right, Exercise Price of Warrants or Rights (in Dollars per share)			$ 33.11		$ 33.11
Warrants Not Settleable in Cash, Fair Value Disclosure			$ 134,000		$ 134,000
Debt Instrument, Interest Rate, Stated Percentage			10.50%		10.50%
London Interbank Offered Rate (LIBOR) [Member] \| Loan Agreement [Member] \| Oxford Finance [Member]
Secured Promissory Note Payable to Oxford Finance (Details) [Line Items]
Debt Instrument, Description of Variable Rate Basis		30-day U.S. LIBOR plus 6.17%
Debt Instrument, Basis Spread on Variable Rate		6.17%
Warrant [Member] \| Common Stock [Member] \| Loan Agreement [Member] \| Oxford Finance [Member]
Secured Promissory Note Payable to Oxford Finance (Details) [Line Items]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in Shares)			10,914		10,914
Class of Warrant or Right, Exercise Price of Warrants or Rights (in Dollars per share)			$ 22.99		$ 22.99
Warrants Not Settleable in Cash, Fair Value Disclosure			$ 70,000		$ 70,000
Debt Conversion, Converted Instrument, Issuance Date					Feb. 13, 2018