Note 7 - Nil Coupon Non-redeemable Convertible Unsecured Loan Notes (Details Textual) $ / shares in Units, $ in Thousands	12 Months Ended
Dec. 31, 2020 USD ($) $ / shares	Dec. 31, 2019 USD ($)
Share Price (in dollars per share)	$ 3.88
Unsecured Debt [Member] \| NIL Coupon Non-redeemable Convertible Unsecured Loan Notes [Member]
Debt Instrument, Face Amount \| $	$ 76	$ 76
Debt Instrument, Convertible, Number of Equity Instruments	6,715
Share Price (in dollars per share)	$ 3.88
Debt Instrument, Convertible, Carrying Amount of Equity Component \| $	$ 26
Debt Instrument, Interest Rate, Stated Percentage	0.00%
Debt Instrument, Repurchase Amount \| $	$ 0	$ 0
Unsecured Debt [Member] \| NIL Coupon Non-redeemable Convertible Unsecured Loan Notes [Member] \| Minimum [Member]
Debt Instrument, Convertible, Conversion Price (in dollars per share)	$ 6.50
Unsecured Debt [Member] \| NIL Coupon Non-redeemable Convertible Unsecured Loan Notes [Member] \| Maximum [Member]
Debt Instrument, Convertible, Conversion Price (in dollars per share)	$ 11.43

The carrying amount of the equity component of convertible debt which may be settled in cash upon conversion.

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The price per share of the conversion feature embedded in the debt instrument.

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The number of equity instruments that the holder of the debt instrument would receive if the debt was converted to equity.

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Face (par) amount of debt instrument at time of issuance.

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

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Fair value amount of debt instrument that was repurchased.

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Price of a single share of a number of saleable stocks of a company.

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