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Note 1 - Summary of Significant Accounting Policies - Breakdown of Investments (Details) - USD ($) $ in Thousands | Dec. 31, 2019 | Dec. 31, 2018
--- | --- | ---
Total Investments | $ 9,894 | $ 8,961
Economic Development Loan Pools [Member] |  |
Cost Method | 24 | 34
Other Cost Method [Member] |  |
Cost Method | 73 | 123
Partnerships [Member] |  |
Equity Method Partnerships | 27 | 26
Debt Securities [Member] |  |
Marketable Securities Classified as Available-for-Sale | 8,184 | 7,484
Equity Securities [Member] |  |
Marketable Securities Classified as Available-for-Sale | $ 1,586 | $ 1,294

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