Note 3 - Mergers and Acquisitions - Cost and Allocation of Purchase Price (Details) (Parentheticals) - $ / shares	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
MBI Stock Options Outstanding (in shares)	780,080	831,080	998,480
MBI Stock Options Strike Price (in dollars per share)	$ 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=109197908&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=109197908&loc=d3e5070-113901

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