Note 3 - Long-term Borrowings - Long-term Borrowings (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
	$ 1,702	$ 1,656
Current portion of long-term borrowing
Non-current portion of long-term borrowing	1,702	1,656
Notes Payable, Other Payables [Member]
Long-term borrowings, gross	1,995	1,995
Accrued interest – long term	71	47
Debt instrument, unamortized discount	$ (364)	$ (386)

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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