Loans and Asset Quality - Schedule of Allowance of Loan Losses By Category (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2020	Dec. 31, 2019
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	$ 13,937	$ 12,524
Provision for Loan Losses	3,618	1,810
Loans Charged-off	(1,584)	(1,219)
Recoveries	221	822
Ending Balance	16,192	13,937
Real estate \| Commercial real estate
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	3,454	3,081
Provision for Loan Losses	1,135	373
Loans Charged-off	0	0
Recoveries	0	0
Ending Balance	4,589	3,454
Real estate \| One-to-four family residential
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	3,323	3,146
Provision for Loan Losses	705	216
Loans Charged-off	0	(44)
Recoveries	8	5
Ending Balance	4,036	3,323
Real estate \| Construction and development
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	1,211	951
Provision for Loan Losses	188	172
Loans Charged-off	(14)	0
Recoveries	1	88
Ending Balance	1,386	1,211
Commercial and industrial
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	5,175	4,604
Provision for Loan Losses	896	850
Loans Charged-off	(1,316)	(864)
Recoveries	83	585
Ending Balance	4,838	5,175
SBA PPP, net of deferred income
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	0	0
Provision for Loan Losses	480	0
Loans Charged-off	0	0
Recoveries	0	0
Ending Balance	480	0
Tax-exempt
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	334	372
Provision for Loan Losses	114	(38)
Loans Charged-off	0	0
Recoveries	0	0
Ending Balance	448	334
Consumer
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	440	370
Provision for Loan Losses	100	237
Loans Charged-off	(254)	(311)
Recoveries	129	144
Ending Balance	$ 415	$ 440

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

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

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Amount of credit loss expense (reversal of expense) for financing receivable.

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