Note 2 - Mergers and Acquisitions - Consideration Paid and Goodwill (Details) - USD ($)				9 Months Ended
		Jul. 01, 2018	Jun. 29, 2018	Sep. 30, 2018	Dec. 31, 2017	Sep. 30, 2017
ASSETS
Cash and due from banks				$ 4,586,326
Interest-bearing deposits at financial institutions				62,924,396
Securities				4,845,441
Loans/leases receivable, net				477,336,699
Bank-owned life insurance				7,091,883
Premises and equipment				6,091,978
Restricted investment securities				3,654,200
Core deposit intangible				8,208,728
Other assets				989,056
Total assets acquired				575,728,707
LIABILITIES
Deposits				439,579,328
Short-term borrowings				1,143,478
FHLB advances				73,610,427
Other borrowings				9,543,810
Other liabilities				8,408,464
Total liabilities assumed				532,285,507
Net assets acquired				43,443,200
Consideration paid:
Cash	[1]			8,333,535
Common stock				80,637,194
Total consideration paid				88,970,729
Goodwill				$ 73,618,426	$ 28,334,092	$ 13,110,913
Springfield Bancshares
ASSETS
Cash and due from banks		$ 4,586,326
Interest-bearing deposits at financial institutions		62,924,396
Securities		4,845,441
Loans/leases receivable, net		477,336,699
Bank-owned life insurance		7,091,883
Premises and equipment		6,091,978
Restricted investment securities		3,654,200
Core deposit intangible		8,208,728
Other assets		989,056
Total assets acquired		575,728,707
LIABILITIES
Deposits		439,579,328
Short-term borrowings		1,143,478
FHLB advances		73,610,427
Other borrowings		9,543,810
Other liabilities		8,408,464
Total liabilities assumed		532,285,507
Net assets acquired		43,443,200
Consideration paid:
Cash		8,333,535
Common stock		80,637,194	$ 80,600,000
Total consideration paid		88,970,729	$ 89,000,000
Goodwill		$ 45,527,529

[1] Net cash paid at closing totalted $3,747,209