Allowance for Loan Losses - Summary of Changes in Allowance for Loan Losses, by Portfolio Type (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Summary of changes in allowance for loan losses, by portfolio type [Roll Forward]
Beginning allowance	$ 9,225	$ 11,114	$ 9,415
Charge-offs	(1,889)	(6,362)	(2,914)
Recoveries	2,086	651	908
Provision for loan losses	1,354	3,822	3,705
Ending allowance	10,776	9,225	11,114
Real Estate
Summary of changes in allowance for loan losses, by portfolio type [Roll Forward]
Beginning allowance	5,516	6,497	6,642
Charge-offs	(503)	(1,324)	(1,617)
Recoveries	202	260	466
Provision for loan losses	2,407	83	1,006
Ending allowance	7,622	5,516	6,497
Real Estate \| Construction & land development
Summary of changes in allowance for loan losses, by portfolio type [Roll Forward]
Beginning allowance	628	1,232	962
Charge-offs	0	0	0
Recoveries	3	43	4
Provision for loan losses	(50)	(647)	266
Ending allowance	581	628	1,232
Real Estate \| Farmland
Summary of changes in allowance for loan losses, by portfolio type [Roll Forward]
Beginning allowance	5	19	54
Charge-offs	0	0	0
Recoveries	0	0	0
Provision for loan losses	36	(14)	(35)
Ending allowance	41	5	19
Real Estate \| 1- 4 Family
Summary of changes in allowance for loan losses, by portfolio type [Roll Forward]
Beginning allowance	1,078	1,204	1,771
Charge-offs	(99)	(33)	(244)
Recoveries	90	92	45
Provision for loan losses	(158)	(185)	(368)
Ending allowance	911	1,078	1,204
Real Estate \| Multifamily
Summary of changes in allowance for loan losses, by portfolio type [Roll Forward]
Beginning allowance	994	591	557
Charge-offs	0	0	0
Recoveries	20	40	401
Provision for loan losses	304	363	(367)
Ending allowance	1,318	994	591
Real Estate \| Non-farm non-residential
Summary of changes in allowance for loan losses, by portfolio type [Roll Forward]
Beginning allowance	2,811	3,451	3,298
Charge-offs	(404)	(1,291)	(1,373)
Recoveries	89	85	16
Provision for loan losses	2,275	566	1,510
Ending allowance	4,771	2,811	3,451
Non-Real Estate
Summary of changes in allowance for loan losses, by portfolio type [Roll Forward]
Beginning allowance	3,709	4,617	2,773
Charge-offs	(1,386)	(5,038)	(1,297)
Recoveries	1,884	391	442
Provision for loan losses	(1,053)	3,739	2,699
Ending allowance	3,154	3,709	4,617
Non-Real Estate \| Agricultural
Summary of changes in allowance for loan losses, by portfolio type [Roll Forward]
Beginning allowance	187	74	16
Charge-offs	(300)	(162)	(83)
Recoveries	26	138	113
Provision for loan losses	426	137	28
Ending allowance	339	187	74
Non-Real Estate \| Commercial and industrial
Summary of changes in allowance for loan losses, by portfolio type [Roll Forward]
Beginning allowance	2,377	3,543	2,527
Charge-offs	(179)	(3,629)	(579)
Recoveries	1,642	30	146
Provision for loan losses	(1,931)	2,433	1,449
Ending allowance	1,909	2,377	3,543
Non-Real Estate \| Consumer and other
Summary of changes in allowance for loan losses, by portfolio type [Roll Forward]
Beginning allowance	1,125	972	230
Charge-offs	(907)	(1,247)	(635)
Recoveries	216	223	183
Provision for loan losses	457	1,177	1,194
Ending allowance	891	1,125	972
Non-Real Estate \| Unallocated
Summary of changes in allowance for loan losses, by portfolio type [Roll Forward]
Beginning allowance	20	28	0
Charge-offs	0	0	0
Recoveries	0	0	0
Provision for loan losses	(5)	(8)	28
Ending allowance	$ 15	$ 20	$ 28

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.

+ References

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- Definition

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

+ References

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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.

+ References

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- Definition

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

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