Note 6 - Loans Receivable, Net and Allowance for Loan Losses (Details Textual)	3 Months Ended	9 Months Ended
Sep. 30, 2020 USD ($)	Sep. 30, 2019 USD ($)	Sep. 30, 2020 USD ($)	Sep. 30, 2019 USD ($)	Dec. 31, 2019 USD ($)
Troubled Debt Restructuring, Number of Contracts	2		2		2
Financing Receivable, Troubled Debt Restructuring	$ 150,000		$ 150,000		$ 151,000
Financing Receivable, Troubled Debt Restructuring, Commitment to Lend	0		0
Loans and Leases Receivable, Gross, Total	350,867,000		350,867,000		249,767,000
Impaired Financing Receivable, Interest Income, Cash Basis Method, Total	0	$ 0	0	$ 0
Loans and Leases Receivable, Impaired, Interest Lost on Nonaccrual Loans	4,000	$ 18,000	10,000	$ 27,000
Nonperforming Financial Instruments [Member]
Loans and Leases Receivable, Gross, Total	$ 1,100,000		$ 1,100,000		$ 362,000

The total number of troubled debt restructurings.

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- Definition

Amount of financing receivable modified as troubled debt restructuring.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953676-111524

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-Section 50
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-URI http://asc.fasb.org/extlink&oid=121585226&loc=d3e18845-111554

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Amount of interest income recognized on a cash-basis method of accounting that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
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-Paragraph 15
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- Definition

Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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-SubTopic 10
-Section 45
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- Definition

Amount of unfunded portion of contractual agreement to lend funds to borrower for financing receivable modified as troubled debt restructuring.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=121585226&loc=d3e18794-111554

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- Definition

Reflects the amount of additional interest income that would have been recorded if impaired or nonperforming loans were instead current, in compliance with their original terms, and outstanding throughout the reporting period or since origination (if held for part of the period).

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