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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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