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Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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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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Amount of increase in allowance for credit loss on financing receivable from recovery.

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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 writeoff of financing receivable, charged against allowance for credit loss.

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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 expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value.

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Loans and Allowance for Credit Losses - Loans - Allowance by Loan Segment (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2021	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2021	Dec. 31, 2020
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance, beginning of year				$ 1,476				$ 2,066	$ 1,476	$ 2,066
Impact of ASC 326 adoption	$ 1,574								1,574
Charged off									(253)	(392)
Recoveries									648	491
Provision for loan losses	(382)	$ (122)	$ (67)	(404)	$ (427)	$ (669)	$ 487	(80)	(975)	(689)
Balance, end of year	2,470				1,476				2,470	1,476
Individually evaluated for impairment:
Individually evaluated for impairment, Balance in allowance	10				11				10	11
Individually evaluated for impairment, Related loan balance	36				4,664				36	4,664
Collectively evaluated for impairment:
Collectively evaluated for impairment, Balance in allowance	2,460				1,465				2,460	1,465
Collectively evaluated for impairment, Related loan balance	210,356				249,108				210,356	249,108
Real Estate Loan
Individually evaluated for impairment:
Individually evaluated for impairment, Balance in allowance	10				11				10	11
Construction And Land Development [Member] \| Real Estate Loan
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance, beginning of year				9				24	9	24
Impact of ASC 326 adoption	16								16
Provision for loan losses									(20)	(15)
Balance, end of year	5				9				5	9
Collectively evaluated for impairment:
Collectively evaluated for impairment, Balance in allowance	5				9				5	9
Collectively evaluated for impairment, Related loan balance	4,087				2,553				4,087	2,553
Farmland \| Real Estate Loan
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance, beginning of year				2				2	2	2
Impact of ASC 326 adoption	9								9
Balance, end of year	11				2				11	2
Collectively evaluated for impairment:
Collectively evaluated for impairment, Balance in allowance	11				2				11	2
Collectively evaluated for impairment, Related loan balance	342				350				342	350
Single-family \| Real Estate Loan
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance, beginning of year				513				849	513	849
Impact of ASC 326 adoption	854								854
Recoveries									408	266
Provision for loan losses									(418)	(602)
Balance, end of year	1,357				513				1,357	513
Individually evaluated for impairment:
Individually evaluated for impairment, Balance in allowance	10				11				10	11
Individually evaluated for impairment, Related loan balance	36				132				36	132
Collectively evaluated for impairment:
Collectively evaluated for impairment, Balance in allowance	1,347				513				1,347	513
Collectively evaluated for impairment, Related loan balance	78,083				82,388				78,083	82,388
Multi-family \| Real Estate Loan
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance, beginning of year				39				40	39	40
Impact of ASC 326 adoption	63								63
Provision for loan losses									3	(1)
Balance, end of year	105				39				105	39
Collectively evaluated for impairment:
Collectively evaluated for impairment, Balance in allowance	105				39				105	39
Collectively evaluated for impairment, Related loan balance	5,428				6,105				5,428	6,105
Commercial and industrial \| Commercial and Industrial
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance, beginning of year				67				69	67	69
Impact of ASC 326 adoption	120								120
Recoveries										20
Provision for loan losses									(72)	(22)
Balance, end of year	115				67				115	67
Individually evaluated for impairment:
Individually evaluated for impairment, Related loan balance					4,493					4,493
Collectively evaluated for impairment:
Collectively evaluated for impairment, Balance in allowance	115				67				115	67
Collectively evaluated for impairment, Related loan balance	10,003				6,307				10,003	6,307
Commercial \| Real Estate Loan
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance, beginning of year				218				241	218	241
Impact of ASC 326 adoption	199								199
Provision for loan losses									(139)	(23)
Balance, end of year	278				218				278	218
Collectively evaluated for impairment:
Collectively evaluated for impairment, Balance in allowance	278				218				278	218
Collectively evaluated for impairment, Related loan balance	48,729				57,027				48,729	57,027
Commercial \| Commercial and Industrial
Collectively evaluated for impairment:
Collectively evaluated for impairment, Related loan balance					9,912					9,912
SBA Guaranty \| Commercial and Industrial
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance, beginning of year				48				25	48	25
Impact of ASC 326 adoption	(6)								(6)
Provision for loan losses									(12)	23
Balance, end of year	30				48				30	48
Collectively evaluated for impairment:
Collectively evaluated for impairment, Balance in allowance	30				48				30	48
Collectively evaluated for impairment, Related loan balance	6,397				7,200				6,397	7,200
Comm SBA PPP \| Commercial and Industrial
Collectively evaluated for impairment:
Collectively evaluated for impairment, Related loan balance	1,047								1,047
Consumer and Indirect \| Consumer Loans
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance, beginning of year				11				11	11	11
Impact of ASC 326 adoption	46								46
Charged off									(2)
Recoveries										6
Provision for loan losses									(19)	(6)
Balance, end of year	36				11				36	11
Individually evaluated for impairment:
Individually evaluated for impairment, Balance in allowance					11					11
Individually evaluated for impairment, Related loan balance					39					39
Collectively evaluated for impairment:
Collectively evaluated for impairment, Balance in allowance	36								36
Collectively evaluated for impairment, Related loan balance	2,090				3,024				2,090	3,024
Automobile \| Consumer Loans
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance, beginning of year				$ 569				$ 805	569	805
Impact of ASC 326 adoption	273								273
Charged off									(251)	(392)
Recoveries									240	199
Provision for loan losses									(298)	(43)
Balance, end of year	533				569				533	569
Collectively evaluated for impairment:
Collectively evaluated for impairment, Balance in allowance	533				569				533	569
Collectively evaluated for impairment, Related loan balance	$ 54,150				$ 74,242				$ 54,150	$ 74,242