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Note 14 - Concentrations of Credit Risk (Details Textual) - Credit Concentration Risk [Member] - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Commercial Real Estate Loans [Member]
Concentration Risk, Percentage	51.00%	50.00%
Concentration Risk, Credit Risk, Financial Instrument, Maximum Exposure	$ 393,115	$ 365,373
College Housing and Professional Office Buildings [Member]
Concentration Risk, Percentage	25.00%	25.00%
Concentration Risk, Credit Risk, Financial Instrument, Maximum Exposure	$ 189,421	$ 181,705
Residential [Member]
Concentration Risk, Percentage	24.00%	25.00%
Concentration Risk, Credit Risk, Financial Instrument, Maximum Exposure	$ 181,782	$ 181,472

X

- Definition

Maximum amount of loss due to credit risk that, based on the gross fair value of the financial instrument, the entity would incur if parties to the financial instruments that make up the concentration failed completely to perform according to the terms of the contracts and the collateral or other security, if any, for the amount due proved to be of no value to the entity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 21
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121572278&loc=d3e13537-108611

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X

- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 42
-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e9054-108599

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-URI http://asc.fasb.org/extlink&oid=99393423&loc=d3e6404-108592

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