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Exercise price per share or per unit of warrants or rights outstanding.

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The value of the financial instrument(s) that the original debt is being converted into in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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Amount of payment greater than the preceding installment payments to be paid at final maturity date of debt.

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Amount of the cost of borrowed funds accounted for as interest expense for debt.

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Note 10 - Secured Promissory Note Payable to Oxford Finance (Details Textual) - USD ($)			12 Months Ended
	Nov. 04, 2019	Dec. 22, 2016	Dec. 31, 2019	Dec. 31, 2018	Feb. 13, 2018
Debt Conversion, Converted Instrument, Amount				$ 35,577,000
Amortization of Debt Issuance Costs	$ 98,000
Legal Fees	$ 2,000
Warrants in Connection with Loan Agreement [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights		7,563			10,914
Class of Warrant or Right, Exercise Price of Warrants or Rights		$ 33.11			$ 22.99
Warrants Not Settleable in Cash, Fair Value Disclosure		$ 134,000			$ 70,000
Loan Agreement [Member] \| Oxford Finance [Member]
Long-term Debt, Gross		$ 5,000,000
Debt Instrument, Term		4 years
Debt Instrument, Periodic Payment Terms, Balloon Payment to be Paid		$ 325,000
Debt Conversion, Converted Instrument, Amount		$ 250,000
Debt Instrument, Interest Rate, Effective Percentage					10.50%
Interest Expense, Debt, Total			311,000	526,000
Interest Paid, Including Capitalized Interest, Operating and Investing Activities, Total			$ 223,000	$ 356,000
Loan Agreement [Member] \| Oxford Finance [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument, Basis Spread on Variable Rate		6.17%