Note 1 - Nature of Operations and Summary of Significant Accounting Policies - Contract Liabilities (Details) - USD ($) $ in Thousands |
Dec. 31, 2019 |
Dec. 31, 2018 |
|---|---|---|
| Contract Liabilities - Customer Deposits | $ 2,071 | $ 1,950 |
| Contract Liabilities - Guaranteed Returns | $ 56 | $ 383 |