Allowance for Loan Losses - Summary of Changes in Allowance for Loan Losses, by Portfolio Type (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Allowance for Loan and Lease Losses [Roll Forward]
Beginning allowance			$ 10,776	$ 9,225
Charge-offs			(2,936)	(1,210)
Recoveries			242	1,994
Provision for Loan and Lease Losses	$ 1,727	$ 372	4,148	568
Ending allowance	12,230	10,577	12,230	10,577
Real Estate
Allowance for Loan and Lease Losses [Roll Forward]
Beginning allowance			7,622	5,516
Charge-offs			(1,367)	(503)
Recoveries			40	198
Provision for Loan and Lease Losses			1,747	1,975
Ending allowance	8,042	7,186	8,042	7,186
Real Estate \| Construction & land development
Allowance for Loan and Lease Losses [Roll Forward]
Beginning allowance			581	628
Charge-offs			0	0
Recoveries			0	3
Provision for Loan and Lease Losses			(58)	(22)
Ending allowance	523	609	523	609
Real Estate \| Farmland
Allowance for Loan and Lease Losses [Roll Forward]
Beginning allowance			41	5
Charge-offs			0	0
Recoveries			0	0
Provision for Loan and Lease Losses			5	7
Ending allowance	46	12	46	12
Real Estate \| 1- 4 Family
Allowance for Loan and Lease Losses [Roll Forward]
Beginning allowance			911	1,078
Charge-offs			(522)	(99)
Recoveries			35	87
Provision for Loan and Lease Losses			408	(275)
Ending allowance	832	791	832	791
Real Estate \| Multifamily
Allowance for Loan and Lease Losses [Roll Forward]
Beginning allowance			1,318	994
Charge-offs			0	0
Recoveries			0	20
Provision for Loan and Lease Losses			(323)	232
Ending allowance	995	1,246	995	1,246
Real Estate \| Non-farm non-residential
Allowance for Loan and Lease Losses [Roll Forward]
Beginning allowance			4,771	2,811
Charge-offs			(845)	(404)
Recoveries			5	88
Provision for Loan and Lease Losses			1,715	2,033
Ending allowance	5,646	4,528	5,646	4,528
Non-Real Estate
Allowance for Loan and Lease Losses [Roll Forward]
Beginning allowance			3,154	3,709
Charge-offs			(1,569)	(707)
Recoveries			202	1,796
Provision for Loan and Lease Losses			2,401	(1,407)
Ending allowance	4,188	3,391	4,188	3,391
Non-Real Estate \| Agricultural
Allowance for Loan and Lease Losses [Roll Forward]
Beginning allowance			339	187
Charge-offs			(40)	(60)
Recoveries			0	12
Provision for Loan and Lease Losses			(177)	276
Ending allowance	122	415	122	415
Non-Real Estate \| Commercial and industrial
Allowance for Loan and Lease Losses [Roll Forward]
Beginning allowance			1,909	2,377
Charge-offs			(598)	(179)
Recoveries			21	1,629
Provision for Loan and Lease Losses			671	(2,167)
Ending allowance	2,003	1,660	2,003	1,660
Non-Real Estate \| Consumer and other
Allowance for Loan and Lease Losses [Roll Forward]
Beginning allowance			891	1,125
Charge-offs			(931)	(468)
Recoveries			181	155
Provision for Loan and Lease Losses			1,922	469
Ending allowance	2,063	1,281	2,063	1,281
Non-Real Estate \| Unallocated
Allowance for Loan and Lease Losses [Roll Forward]
Beginning allowance			15	20
Charge-offs			0	0
Recoveries			0	0
Provision for Loan and Lease Losses			(15)	15
Ending allowance	$ 0	$ 35	$ 0	$ 35

Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

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- Definition

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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Amount of expense related to estimated loss from loan and lease transactions.

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