Note 6 - Goodwill and Intangibles - Core Deposit Intangibles (Details) - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2017	Dec. 31, 2016
Balance at the beginning of the period	$ 7,381,213	$ 1,471,409
Amortization expense	(1,000,561)	(442,849)	$ (199,512)
Balance at the end of the period	9,078,953	7,381,213	1,471,409
Net book value	9,078,953	7,381,213	1,471,409	$ 9,078,953	$ 7,381,213
Core Deposits [Member]
Balance at the beginning of the period	7,381,213	1,471,410
Amortization expense	(1,000,561)	(442,850)
Balance at the end of the period	9,078,953	7,381,213	1,471,410
Gross carrying amount				11,046,081	8,347,780
Accumulated amortization				(1,967,128)	(966,567)
Net book value	7,381,213	7,381,213	$ 1,471,410	$ 9,078,953	$ 7,381,213
Core Deposits [Member] | Guaranty Bank [Member]
Core deposit intangible from acquisition	2,698,301
Core Deposits [Member] | Community State Bank [Member]
Core deposit intangible from acquisition		$ 6,352,653