Note 5 - Line of Credit and Long-term Debt - Future Principal Payments of Long-term Debt (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Less: Current portion of long-term debt	$ (3,133)	$ 0
Long-term debt	12,032	$ 0
Term Loan [Member] \| Wells Fargo Bank, N.A. [Member]
Remainder of 2020	1,588
2021	3,176
2022	3,176
2023	3,176
2024	4,234
Total future principal payments	15,350
Less: Unamortized debt issuance costs	(185)
Less: Current portion of long-term debt	(3,133)
Long-term debt	$ 12,032

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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