Note 19 - Quarterly Results of Operations (Unaudited) - Quarterly Results of Operations (Unaudited) (Details) - USD ($)	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Total interest income	$ 37,878,086	$ 33,840,865	$ 32,453,268	$ 31,345,099	$ 32,235,657	$ 26,816,735	$ 23,913,284	$ 23,502,059
Total interest expense	6,084,733	5,284,517	4,406,571	3,676,216	2,955,992	3,185,958	2,904,471	2,904,537	$ 19,452,037	$ 11,950,958	$ 13,706,529
Net interest income	31,793,353	28,556,348	28,046,697	27,668,883	29,279,665	23,630,777	21,008,813	20,597,522	116,065,281	94,516,777	76,296,724
Provision for loan/lease losses	2,255,381	2,086,436	2,022,993	2,105,109	2,599,345	1,607,986	1,197,850	2,072,985	8,469,919	7,478,166	6,870,900
Noninterest income	9,714,717	6,701,303	6,782,518	7,283,754	7,028,600	10,423,401	6,762,401	6,822,473	30,482,292	31,036,875	24,363,321
Noninterest expense	31,351,204	23,395,747	21,404,629	21,273,117	22,307,178	24,480,483	17,743,753	16,954,498	97,424,697	81,485,912	73,192,022
Income before taxes	7,901,485	9,775,468	11,401,593	11,574,411	11,401,742	7,965,709	8,829,611	8,392,512	40,652,957	36,589,574	20,597,123
Income Tax Expense (Benefit)	(2,000,105)	1,921,533	2,635,576	2,389,446	2,872,412	1,858,208	2,153,144	2,019,023	4,946,450	8,902,787	3,669,242
Net income (loss)	$ 9,901,590	$ 7,853,935	$ 8,766,017	$ 9,184,965	$ 8,529,330	$ 6,107,501	$ 6,676,467	$ 6,373,489	$ 35,706,507	$ 27,686,787	$ 16,927,881
Basic (in dollars per share)	$ 0.72	$ 0.60	$ 0.67	$ 0.70	$ 0.65	$ 0.47	$ 0.54	$ 0.54	$ 2.68	$ 2.20	$ 1.64
Diluted (in dollars per share)	$ 0.70	$ 0.58	$ 0.65	$ 0.68	$ 0.64	$ 0.46	$ 0.53	$ 0.53	$ 2.61	$ 2.17	$ 1.61