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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
	Feb. 13, 2018	Dec. 22, 2016	Mar. 31, 2018	Mar. 31, 2017
Secured Promissory Note Payable to Oxford Finance (Details) [Line Items]
Debt Instrument, Interest Rate, Stated Percentage			8.00%
Interest Paid, Including Capitalized Interest, Operating and Investing Activities			$ 95,000	$ 57,000
Debt Conversion, Converted Instrument, Amount	$ 14,200,000		250,000
Oxford Finance [Member]
Secured Promissory Note Payable to Oxford Finance (Details) [Line Items]
Debt Instrument, Interest Rate Terms		30-day U.S. LIBOR plus 6.17%
Debt Instrument, Interest Rate, Effective Percentage		6.17%
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
Interest Expense, Debt			130,000	126,000
Interest Paid, Including Capitalized Interest, Operating and Investing Activities			$ 95,000	$ 57,000
Convertible Preferred Stock [Member] \| Series C Preferred Stock [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
Class of Warrant or Right, Exercise Price of Warrants or Rights (in Dollars per share)			$ 33.11
Warrants Not Settleable in Cash, Fair Value Disclosure			$ 134,000
Debt Instrument, Interest Rate, Stated Percentage			10.50%
Warrant [Member] \| Common Stock [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
Class of Warrant or Right, Exercise Price of Warrants or Rights (in Dollars per share)			$ 22.99
Warrants Not Settleable in Cash, Fair Value Disclosure			$ 70,000
Debt Conversion, Converted Instrument, Issuance Date			Feb. 13, 2018