Note 9 - Fair Value of Assets and Liabilities - Assets Reported on the Consolidated Balance Sheets, on a Recurring Basis, at Their Fair Value (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Investment securities available-for-sale (Note 3)	$ 167,577	$ 136,131
Loans held for sale	6,564	4,890
Interest rate derivatives, assets	4,239	1,422
Interest rate derivatives, liabilities	4,239	1,422
Fair Value, Inputs, Level 1 [Member]
Loans held for sale	6,564	4,890
Interest rate derivatives, assets	0	0
Interest rate derivatives, liabilities	0	0
Fair Value, Inputs, Level 2 [Member]
Loans held for sale	0	0
Interest rate derivatives, assets	4,239	1,422
Interest rate derivatives, liabilities	4,239	1,422
Fair Value, Inputs, Level 3 [Member]
Loans held for sale	0	0
Interest rate derivatives, assets	0	0
Interest rate derivatives, liabilities	0	0
US Government Corporations and Agencies Securities [Member]
Investment securities available-for-sale (Note 3)	0	3,310
US Government Corporations and Agencies Securities [Member] \| Fair Value, Inputs, Level 1 [Member]
Investment securities available-for-sale (Note 3)	0	0
US Government Corporations and Agencies Securities [Member] \| Fair Value, Inputs, Level 2 [Member]
Investment securities available-for-sale (Note 3)	0	3,310
US Government Corporations and Agencies Securities [Member] \| Fair Value, Inputs, Level 3 [Member]
Investment securities available-for-sale (Note 3)	0	0
US States and Political Subdivisions Debt Securities [Member]
Investment securities available-for-sale (Note 3)	88,411	69,626
US States and Political Subdivisions Debt Securities [Member] \| Fair Value, Inputs, Level 1 [Member]
Investment securities available-for-sale (Note 3)	0	0
US States and Political Subdivisions Debt Securities [Member] \| Fair Value, Inputs, Level 2 [Member]
Investment securities available-for-sale (Note 3)	88,411	69,626
US States and Political Subdivisions Debt Securities [Member] \| Fair Value, Inputs, Level 3 [Member]
Investment securities available-for-sale (Note 3)	0	0
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Investment securities available-for-sale (Note 3)	67,915	48,237
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member] \| Fair Value, Inputs, Level 1 [Member]
Investment securities available-for-sale (Note 3)	0	0
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member] \| Fair Value, Inputs, Level 2 [Member]
Investment securities available-for-sale (Note 3)	67,915	48,237
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member] \| Fair Value, Inputs, Level 3 [Member]
Investment securities available-for-sale (Note 3)	0	0
Collateralized Mortgage Obligations [Member]
Investment securities available-for-sale (Note 3)	5,616	8,481
Collateralized Mortgage Obligations [Member] \| Fair Value, Inputs, Level 1 [Member]
Investment securities available-for-sale (Note 3)	0	0
Collateralized Mortgage Obligations [Member] \| Fair Value, Inputs, Level 2 [Member]
Investment securities available-for-sale (Note 3)	5,616	8,481
Collateralized Mortgage Obligations [Member] \| Fair Value, Inputs, Level 3 [Member]
Investment securities available-for-sale (Note 3)	0	0
US Government Small Business Administration Securities [Member]
Investment securities available-for-sale (Note 3)	5,635	6,477
US Government Small Business Administration Securities [Member] \| Fair Value, Inputs, Level 1 [Member]
Investment securities available-for-sale (Note 3)	0	0
US Government Small Business Administration Securities [Member] \| Fair Value, Inputs, Level 2 [Member]
Investment securities available-for-sale (Note 3)	5,635	6,477
US Government Small Business Administration Securities [Member] \| Fair Value, Inputs, Level 3 [Member]
Investment securities available-for-sale (Note 3)	$ 0	$ 0

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(6))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=121558606&loc=SL82898722-210454

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121553693&loc=d3e26610-111562

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (aa)
-URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27161-111563

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-SubTopic 10
-Section 50
-Paragraph 4B
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