Note 8 - Advances from the Federal Home Loan Bank (Details Textual) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2020	Dec. 31, 2019
Federal Home Loan Bank, Advances, Weighted Average Interest Rate	0.39%	1.70%
Federal Home Loan Bank, Advances, General Debt Obligations, Disclosures, Repayment and Penalties	$ 0	$ 0
Federal Home Loan Bank, Advances, General Debt Obligations, Disclosures, Collateral Pledged	158,500	$ 166,000
Federal Home Loan Bank, Advances, General Debt Obligations, Amount of Available, Unused Funds	$ 53,600

Amount of advances or credit lines available from the Federal Home Loan Bank (FHLB).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22 (b))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.13(3)(a))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822

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- Definition

Amount of the collateral pledged in support of federal home loan bank advances outstanding.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
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- Definition

Amount of repayments and penalties incurred in the satisfaction or roll-over of Federal Home Loan Bank (FHLB) advance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-Section 50
-Paragraph 3
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- Definition

Weighted average interest rate on advances made and reported by Federal Home Loan Bank (FHLBank).

+ References

No definition available.

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