Note 5 - Line of Credit and Long-term Debt - Future Principal Payments of Long-term Debt (Details) - Term Loan [Member] - Wells Fargo Bank, N.A. [Member] $ in Thousands	Mar. 31, 2020 USD ($)
Remainder of 2020	$ 2,117
2021	3,176
2022	3,176
2023	3,176
2024	4,234
Thereafter
Total future principal payments	$ 15,879

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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