Note 2 - Acquisitions - Changes in Accretable Yield (Details) - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Balance at the beginning of the period	$ (9,309,920)
Discount added at acquisition	(2,443,891)	(12,193,588)
Accretion recognized	5,282,604	2,883,668
Balance at the end of the period	(6,471,207)	(9,309,920)
Performing Financial Instruments [Member]
Balance at the beginning of the period	(9,115,614)
Discount added at acquisition	(2,223,989)	(11,916,009)
Accretion recognized	5,059,528	2,800,395
Balance at the end of the period	(6,280,075)	(9,115,614)
Guaranty Bank and Trust Company [Member]
Balance at the beginning of the period
Discount added at acquisition	(2,443,891)
Accretion recognized	80,906
Balance at the end of the period	(2,362,985)
Guaranty Bank and Trust Company [Member] | Performing Financial Instruments [Member]
Balance at the beginning of the period
Discount added at acquisition	(2,223,989)
Accretion recognized	26,836
Balance at the end of the period	(2,197,153)
Community State Bank [Member]
Balance at the beginning of the period	(9,309,920)
Discount added at acquisition		(12,193,588)
Accretion recognized	5,201,698	2,883,668
Balance at the end of the period	(4,108,222)	(9,309,920)
Community State Bank [Member] | Performing Financial Instruments [Member]
Balance at the beginning of the period	(9,115,614)
Discount added at acquisition		(11,916,009)
Accretion recognized	5,032,692	2,800,395
Balance at the end of the period	(4,082,922)	(9,115,614)
Receivables Acquired with Deteriorated Credit Quality [Member]
Balance at the beginning of the period	(194,306)
Discount added at acquisition	(219,902)	(277,579)
Accretion recognized	223,076	83,273
Balance at the end of the period	(191,132)	(194,306)
Receivables Acquired with Deteriorated Credit Quality [Member] | Guaranty Bank and Trust Company [Member]
Balance at the beginning of the period
Discount added at acquisition	(219,902)
Accretion recognized	54,070
Balance at the end of the period	(165,832)
Receivables Acquired with Deteriorated Credit Quality [Member] | Community State Bank [Member]
Balance at the beginning of the period	(194,306)
Discount added at acquisition		(277,579)
Accretion recognized	169,006	83,273
Balance at the end of the period	$ (25,300)	$ (194,306)