Allowance for Loan Losses - Segregated by Class of Loan (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	$ 10,289	$ 6,789	$ 6,863	$ 7,277
Charge-offs	(559)	(588)	(1,456)	(1,687)
Recoveries	184	185	351	486
Provision	1,106	214	5,262	524
Ending balance	11,020	6,600	11,020	6,600
Period end amount allocated to
Individually evaluated for impairment	1,369		1,369		$ 3,149
Collectively evaluated for impairment	9,563		9,563		3,708
Loans
Individually evaluated for impairment	26,395		26,395		23,808
Collectively evaluated for impairment	1,074,708		1,074,708		944,859
Loans	1,101,606		1,101,606		968,814
Purchase credit impaired
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance			6
Ending balance	88		88
Loans
Loans	503		503		147
Construction, land and land development
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	759	12	215	131
Charge-offs	0	0	(4)	(29)
Recoveries	6	7	31	61
Provision	199	156	722	12
Ending balance	964	175	964	175
Period end amount allocated to
Individually evaluated for impairment	0		0		0
Collectively evaluated for impairment	964		964		215
Loans
Individually evaluated for impairment	7,023		7,023		67
Collectively evaluated for impairment	121,150		121,150		95,965
Loans	128,291		128,291		96,097
Construction, land and land development \| Purchase credit impaired
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance			0
Ending balance	0		0
Loans
Loans	118		118		65
Other commercial real estate
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	5,711	4,430	3,908	5,251
Charge-offs	(226)	0	(226)	(119)
Recoveries	3	142	29	183
Provision	127	(559)	1,904	(1,302)
Ending balance	5,615	4,013	5,615	4,013
Period end amount allocated to
Individually evaluated for impairment	728		728		1,939
Collectively evaluated for impairment	4,887		4,887		1,969
Loans
Individually evaluated for impairment	16,329		16,329		18,024
Collectively evaluated for impairment	493,543		493,543		522,181
Loans	509,992		509,992		540,239
Other commercial real estate \| Purchase credit impaired
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance			0
Ending balance	0		0
Loans
Loans	120		120		34
Residential real estate
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	1,631	845	980	1,181
Charge-offs	(144)	(110)	(159)	(757)
Recoveries	120	7	130	166
Provision	317	215	973	367
Ending balance	1,924	957	1,924	957
Period end amount allocated to
Individually evaluated for impairment	74		74		137
Collectively evaluated for impairment	1,845		1,845		837
Loans
Individually evaluated for impairment	2,429		2,429		3,471
Collectively evaluated for impairment	182,673		182,673		191,314
Loans	185,118		185,118		194,796
Residential real estate \| Purchase credit impaired
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance			6
Ending balance	5		5
Loans
Loans	16		16		11
Commercial, financial, & agricultural
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	1,913	1,421	1,657	618
Charge-offs	(153)	(225)	(221)	(350)
Recoveries	1	14	21	31
Provision	346	104	650	1,015
Ending balance	2,107	1,314	2,107	1,314
Period end amount allocated to
Individually evaluated for impairment	567		567		1,073
Collectively evaluated for impairment	1,540		1,540		584
Loans
Individually evaluated for impairment	614		614		2,246
Collectively evaluated for impairment	254,244		254,244		112,077
Loans	254,915		254,915		114,360
Commercial, financial, & agricultural \| Purchase credit impaired
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance			0
Ending balance	0		0
Loans
Loans	57		57		37
Consumer and other
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	275	81	103	96
Charge-offs	(36)	(253)	(846)	(432)
Recoveries	54	15	140	45
Provision	117	298	1,013	432
Ending balance	410	$ 141	410	$ 141
Period end amount allocated to
Individually evaluated for impairment	0		0		0
Collectively evaluated for impairment	327		327		103
Loans
Individually evaluated for impairment	0		0		0
Collectively evaluated for impairment	23,098		23,098		23,322
Loans	23,290		23,290		23,322
Consumer and other \| Purchase credit impaired
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance			0
Ending balance	83		83
Loans
Loans	$ 192		$ 192		$ 0

Loans And Leases, Additional Information

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

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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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The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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The balance of financing receivables that were collectively evaluated for impairment.

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The balance of financing receivables that were individually evaluated for impairment.

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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 before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes 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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