Note 5 - Goodwill and Other Intangible Assets (Details Textual) - USD ($)	1 Months Ended	52 Months Ended
Jul. 31, 2011	Apr. 30, 2019
MidCarolina Financial Corporation [Member]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles	$ 6,556,000
Finite-Lived Intangible Asset, Useful Life (Month)	108 months
MainStreet BancShares, Inc and HomeTown Bankshares Corporation [Member]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles		$ 10,039,000
Finite-Lived Intangible Asset, Useful Life (Month)		120 months

The amount of identifiable intangible assets recognized as of the acquisition date.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 55
-Paragraph 37
-URI http://asc.fasb.org/extlink&oid=121600890&loc=d3e2207-128464

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=121647850&loc=d3e4845-128472

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Balance Type:	debit
Period Type:	instant