Note 20 - Parent Company Only Financial Statements (Details) - Condensed Balance Sheets - USD ($)	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Condensed Balance Sheet Statements, Captions [Line Items]
Cash and due from banks	$ 41,957,855	$ 38,235,019
Interest-bearing deposits at financial institutions	36,098,431	35,334,682
Securities available for sale, at fair value	323,434,982	451,659,630
Premises and equipment, net	37,350,352	36,021,128
Other assets	26,784,392	23,174,994
Total assets	2,593,198,275	2,524,958,100	$ 2,394,952,924
Liabilities:
Other borrowings	110,000,000	150,282,492
Other liabilities	42,484,573	38,653,681
Total liabilities	2,367,312,525	2,380,879,591
Stockholders' Equity:
Common stock	11,761,083	8,074,443
Additional paid-in capital	123,282,851	61,668,968
Retained earnings	92,965,645	77,876,824
Treasury stock		(1,606,510)
Total liabilities and stockholders' equity	2,593,198,275	2,524,958,100
Parent Company [Member]
Condensed Balance Sheet Statements, Captions [Line Items]
Cash and due from banks	3,650,133	4,499,139
Interest-bearing deposits at financial institutions	701	190,127
Securities available for sale, at fair value	1,398,255	1,724,353
Premises and equipment, net	4,502,435	3,160,035
Other assets	12,797,292	6,765,109
Total assets	280,376,933	216,608,863
Liabilities:
Other borrowings		21,745,116
Junior subordinated debentures	38,499,052	40,423,735
Other liabilities	15,992,131	10,361,503
Total liabilities	54,491,183	72,530,354
Stockholders' Equity:
Common stock	11,761,083	8,074,443
Additional paid-in capital	123,282,851	61,668,968
Retained earnings	92,965,645	77,876,824
Accumulated other comprehensive loss	(2,123,829)	(1,935,216)
Treasury stock		(1,606,510)
Total stockholders' equity	225,885,750	144,078,509
Total liabilities and stockholders' equity	280,376,933	216,608,863
Bank Subsidiaries [Member] | Parent Company [Member]
Condensed Balance Sheet Statements, Captions [Line Items]
Investment in subsidiaries	256,709,890	198,881,739
Non-bank Subsidiaries [Member] | Parent Company [Member]
Condensed Balance Sheet Statements, Captions [Line Items]
Investment in subsidiaries	$ 1,318,227	$ 1,388,361