Consolidated Statements of Cash Flows	12 Months Ended
	Dec. 31, 2018 USD ($)		Dec. 31, 2017 USD ($)		Dec. 31, 2016 USD ($)
CASH FLOWS FROM OPERATING ACTIVITIES
Net income	$ 43,119,699		$ 35,706,507		$ 27,686,787
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation	4,450,758		3,948,934		3,424,140
Provision for loan/lease losses	12,658,449		8,469,919		7,478,166
Deferred income taxes	6,292,477		(6,029,555)		(3,066,407)
Stock-based compensation expense	1,443,346		1,187,036		947,174
Deferred compensation expense accrued	1,826,055		1,425,717		1,171,406
Losses (gains) on other real estate owned, net	2,584,890		(151,211)		243,858
Amortization of premiums on securities, net	1,614,426		1,839,196		1,302,962
Securities (gains) losses, net			87,885		(4,592,398)
Loans originated for sale	(57,697,515)		(49,578,773)		(74,329,667)
Proceeds on sales of loans	58,352,712		51,641,668		77,850,553
Gains on sales of residential real estate loans	(900,744)		(408,655)		(431,313)
Gains on sales of government guaranteed portions of loans	(404,852)		(1,163,741)		(3,159,073)
Losses on debt extinguishment, net					4,577,668
Amortization of core deposit intangible	1,692,431		1,000,561		442,850
Accretion of acquisition fair value adjustments, net	(5,527,105)		(4,940,760)		(3,718,160)
Increase in cash value of bank-owned life insurance	(1,631,749)		(1,802,443)		(1,771,396)
Decrease (increase) in other assets	(11,140,958)		726,336		(943,892)
Increase (decrease) in other liabilities	7,538,428		(8,245,340)		10,269,563
Net cash provided by operating activities	64,270,748		33,713,281		43,382,821
CASH FLOWS FROM INVESTING ACTIVITIES
Net decrease (increase) in federal funds sold	3,799,000		(7,940,000)		(1,709,000)
Net decrease (increase) in interest-bearing deposits at financial institutions	(14,508,687)		12,137,820		(12,904,803)
Proceeds from sales of other real estate owned	2,538,865		1,138,520		2,084,696
Activity in securities portfolio:
Purchases	(84,044,869)		(179,785,944)		(179,598,630)
Calls, maturities and redemptions	23,931,014		43,010,478		117,876,284
Paydowns	44,287,054		38,495,801		33,169,638
Sales	1,938,043		71,091,580		134,188,737
Activity in restricted investment securities:
Purchases	(5,409,075)		(4,824,000)		(1,098,200)
Redemptions	3,157,025		515,000		2,450,000
Net increase in loans/leases originated and held for investment	(292,696,750)		(375,226,301)		(187,496,180)
Purchase of premises and equipment	(11,457,086)		(5,760,802)		(6,032,416)
Net cash paid for acquisitions	(5,182,804)		(3,368,909)		(69,905,355)
Net cash used in investing activities	(333,648,270)		(410,516,757)		(168,975,229)
CASH FLOWS FROM FINANCING ACTIVITIES:
Net increase in deposit accounts	271,266,725		385,082,234		302,390,928
Net increase (decrease) in short-term borrowings	13,637,557		(39,080,308)		(104,691,329)
Activity in Federal Home Loan Bank advances:
Term advances	15,080,200		1,600,000
Calls and maturities	(40,000,000)		(8,000,000)		(24,000,000)
Net change in short-term and overnight advances	24,765,000		60,900,000		20,500,000
Prepayments			(4,108,027)		(31,008,668)
Activity in other borrowings:
Proceeds from other borrowings	9,000,000		7,000,000		35,000,000
Calls, maturities and scheduled principal payments	(12,550,000)		(21,000,000)
Prepayments					(69,769,000)
Retirement of junior subordinated debentures					(3,955,000)
Payment of cash dividends on common stock	(3,300,091)		(2,494,260)		(1,981,541)
Net cash provided by financing activities	279,178,544		381,955,146		154,420,080
Net decrease in cash and due from banks	9,801,022		5,151,670		28,827,672
Cash and due from banks, beginning	75,721,663		70,569,993		41,742,321
Cash and due from banks, ending	85,522,685		75,721,663		70,569,993
Supplemental disclosure of cash flow information, cash payments (receipts) for:
Interest	38,781,813		19,053,645		11,926,012
Income/franchise taxes	29,583		13,039,516		10,758,611
Supplemental schedule of noncash investing activities:
Change in accumulated other comprehensive income, unrealized gains on securities available for sale and derivative instruments, net	(3,205,499)		1,092,153		(335,760)
Exchange of shares of common stock in connection with payroll taxes for restricted stock and in connection with stock options exercised	(876,665)		(1,009,797)		(568,875)
Tax benefit of nonqualified stock options exercised					394,149
Transfers of loans to other real estate owned	943,183		9,022,514		51,000
Due to broker for purchases of securities					2,655,492
Tax basis adjustment related to the acquisition of noncontrolling interest in m2 Lease Funds					2,132,415
Increase (decrease) in the fair value of back to back interest rate swap assets and liabilities	17,798,475		2,058,957		(706,244)
Dividends payable	938,710		692,874		522,573
Transfer of equity securities from securities available for sale to other assets at fair value	2,614,260
Fair value of assets acquired:
Cash and due from banks	4,650,731		4,434,511		10,094,645
Federal funds sold					698,000
Interest-bearing deposits at financial institutions	62,924,396		3,953,907		14,730,157
Securities	4,845,441		49,703,419		102,640,029
Loans receivable, net	477,336,699		192,517,677		419,029,277
Bank-owned life insurance	7,091,883
Premises and equipment, net	6,091,978		4,808,343		20,684,880
Restricted investment securities	3,654,200		476,500		1,512,900
Other real estate owned					650,000
Intangibles	10,063,660		2,698,301		6,352,653
Other assets	2,254,778		997,810		5,283,937
Total assets acquired	578,913,766		259,590,468		581,676,478
Fair value of liabilities assumed:
Deposits	439,579,328		212,467,514		486,298,262
Short-term borrowings	1,143,478		13,102,043
FHLB advances	74,539,463		4,108,027		20,368,877
Other borrowings	9,543,810
Junior subordinated debentures			3,857,275
Other liabilities	8,877,991		2,595,883		4,897,564
Total liabilities assumed	533,684,070		236,130,742		511,564,703
Net assets acquired	45,229,696		23,459,726		70,111,775
Consideration paid:
Cash paid	9,833,535	[1]	7,803,420	[1]	80,000,000	[1]
Promissory note	1,500,000
Contingent consideration	2,000,000
Common stock	81,637,166		30,879,485
Total consideration paid	94,970,701		38,682,905		80,000,000
Goodwill	49,741,005		15,223,179		9,888,225
Common Stock Offering 2 [Member]
Activity in other borrowings:
Proceeds from issuance of common stock, net	1,279,153		2,055,507		31,934,690
Springfield Bancshares
Consideration paid:
Cash paid	3,747,209
Goodwill	45,974,931
Guaranty Bank [Member]
Consideration paid:
Cash paid	3,368,909
Goodwill			$ 15,223,179
Bates Companies [Member]
Consideration paid:
Cash paid	1,435,595
Goodwill	3,766,074
Community State Bank [Member]
Fair value of assets acquired:
Premises and equipment, net	20,700,000
Consideration paid:
Cash paid	$ 69,905,355
Goodwill					$ 9,888,225

[1] Net cash paid at closing totaled $1,435,595 for acquisition of the Bates Companies in 2018. Net cash paid at closing totaled $3,747,209 for merger with Springfield Bancshares in 2018. Net cash paid at closing totaled $3,368,909 for acquisition of Guaranty Bank in 2017. Net cash paid at closing totaled $69,905,355 for acquisition of CSB in 2016.