Note 3 - Mergers and Acquisitions - Cost and Allocation of Purchase Price (Details) (Parentheticals) - $ / shares	Dec. 31, 2019	Dec. 31, 2018	Jan. 01, 2018	Dec. 31, 2017	Dec. 31, 2016
MBI Stock Options Outstanding (in shares)	725,300	780,080		831,080	998,480
MBI Stock Options Strike Price (in dollars per share)	$ 12.55	$ 12.74		$ 12.73	$ 12.82
Minden Bancorp [Member]
MBI Stock Options Outstanding (in shares)			17,822
MBI Stock Options Strike Price (in dollars per share)			$ 31.50

Number of options outstanding, including both vested and non-vested options.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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