Note 6 - Goodwill and Intangibles - Goodwill (Details) - USD ($)	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Balance at the beginning of period	$ 28,334,092	$ 13,110,913	$ 3,222,688
Goodwill from acquisition	49,741,005	15,223,179	9,888,225
Balance at the end of period	77,831,902	28,334,092	13,110,913
Springfield Bancshares
Goodwill from acquisition	45,974,931
Bates Companies [Member]
Goodwill from acquisition	3,766,074
Balance at the end of period	3,766,074
Guaranty Bank [Member]
Goodwill from acquisition		$ 15,223,179
Goodwill from acquisition - measurement period adjustment	$ (243,195)
Community State Bank [Member]
Goodwill from acquisition			$ 9,888,225

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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