Note 6 - Goodwill and Intangibles - Goodwill (Details) - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Balance at the beginning of period	$ 13,110,913	$ 3,222,688
Goodwill from acquisition of Guaranty Bank	15,223,179	9,888,225
Balance at the end of period	28,334,092	13,110,913	$ 3,222,688
Guaranty Bank [Member]
Goodwill from acquisition of Guaranty Bank	15,223,179
Community State Bank [Member]
Goodwill from acquisition of Guaranty Bank		$ 9,888,225