Loans - Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Balance	$ 34,340	$ 19,473
(Charge-offs)	(1,058)	(910)
Recoveries	151	273
Provision (Benefit) for Credit Loss Expense	2,122	3,079
Allowance for loan losses, Ending Balance	35,555	21,915
Farmland
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Balance	221
(Charge-offs)	0
Recoveries	0
Provision (Benefit) for Credit Loss Expense	3
Allowance for loan losses, Ending Balance	224
Owner-occupied, nonfarm nonresidential properties
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Balance	3,700
(Charge-offs)	(531)
Recoveries	2
Provision (Benefit) for Credit Loss Expense	(236)
Allowance for loan losses, Ending Balance	2,935
Agricultural production and other loans to farmers
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Balance	24
(Charge-offs)	0
Recoveries	0
Provision (Benefit) for Credit Loss Expense	4
Allowance for loan losses, Ending Balance	28
Commercial and Industrial
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Balance	6,233
(Charge-offs)	(56)
Recoveries	5
Provision (Benefit) for Credit Loss Expense	297
Allowance for loan losses, Ending Balance	6,479
Obligations (other than securities and leases) of states and political subdivisions
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Balance	998
(Charge-offs)	0
Recoveries	0
Provision (Benefit) for Credit Loss Expense	717
Allowance for loan losses, Ending Balance	1,715
Other loans
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Balance	68
(Charge-offs)	0
Recoveries	0
Provision (Benefit) for Credit Loss Expense	5
Allowance for loan losses, Ending Balance	73
Other construction loans and all land development and other land loans
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Balance	1,956
(Charge-offs)	0
Recoveries	0
Provision (Benefit) for Credit Loss Expense	50
Allowance for loan losses, Ending Balance	2,006
Multifamily (5 or more) residential properties
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Balance	2,724
(Charge-offs)	0
Recoveries	0
Provision (Benefit) for Credit Loss Expense	30
Allowance for loan losses, Ending Balance	2,754
Non-owner occupied, nonfarm nonresidential properties
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Balance	8,658
(Charge-offs)	0
Recoveries	0
Provision (Benefit) for Credit Loss Expense	2,668
Allowance for loan losses, Ending Balance	11,326
1-4 Family Construction
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Balance	82
(Charge-offs)	0
Recoveries	0
Provision (Benefit) for Credit Loss Expense	(15)
Allowance for loan losses, Ending Balance	67
Home equity lines of credit
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Balance	985
(Charge-offs)	0
Recoveries	0
Provision (Benefit) for Credit Loss Expense	(142)
Allowance for loan losses, Ending Balance	843
Residential Mortgages secured by first liens
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Balance	4,539
(Charge-offs)	(28)
Recoveries	31
Provision (Benefit) for Credit Loss Expense	(992)
Allowance for loan losses, Ending Balance	3,550
Residential Mortgages secured by junior liens
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Balance	241
(Charge-offs)	0
Recoveries	0
Provision (Benefit) for Credit Loss Expense	(17)
Allowance for loan losses, Ending Balance	224
Other revolving credit plans
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Balance	507
(Charge-offs)	(6)
Recoveries	2
Provision (Benefit) for Credit Loss Expense	24
Allowance for loan losses, Ending Balance	527
Automobile
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Balance	132
(Charge-offs)	(5)
Recoveries	0
Provision (Benefit) for Credit Loss Expense	55
Allowance for loan losses, Ending Balance	182
Other consumer
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Balance	2,962
(Charge-offs)	(315)
Recoveries	48
Provision (Benefit) for Credit Loss Expense	(321)
Allowance for loan losses, Ending Balance	2,374
Commercial, Industrial  and Agricultural
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Balance		8,287
(Charge-offs)		(25)
Recoveries		18
Provision (Benefit) for Credit Loss Expense		2,252
Allowance for loan losses, Ending Balance		10,532
Commercial Mortgages
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Balance		6,952
(Charge-offs)		0
Recoveries		172
Provision (Benefit) for Credit Loss Expense		368
Allowance for loan losses, Ending Balance		7,492
Residential Real Estate
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Balance		1,499
(Charge-offs)		(143)
Recoveries		3
Provision (Benefit) for Credit Loss Expense		99
Allowance for loan losses, Ending Balance		1,458
Consumer
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Balance		2,411
(Charge-offs)		(592)
Recoveries		43
Provision (Benefit) for Credit Loss Expense		276
Allowance for loan losses, Ending Balance		2,138
Credit cards
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Balance	66	84
(Charge-offs)	(33)	(31)
Recoveries	8	1
Provision (Benefit) for Credit Loss Expense	24	58
Allowance for loan losses, Ending Balance	65	112
Overdrafts
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Balance	244	240
(Charge-offs)	(84)	(119)
Recoveries	55	36
Provision (Benefit) for Credit Loss Expense	(32)	26
Allowance for loan losses, Ending Balance	$ 183	$ 183