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

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Loans and Allowance for Loan Losses - Summary of Additional Information Pertaining to the Allowance for Loan Losses (Detail) - USD ($) $ in Thousands	Jun. 30, 2022	Mar. 31, 2022	Dec. 31, 2021	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for impaired loans	$ 90		$ 100
Allowance for non-impaired loans	6,512		6,189
Total allowance for loan losses	6,602	$ 6,357	6,289	$ 6,523	$ 6,563	$ 6,784
Impaired loans	3,982		3,858
Non-impaired loans	658,876		545,979
Total loans	662,858		549,837
Commercial Real Estate Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for non-impaired loans	3,224		3,451
Total allowance for loan losses	3,224	3,402	3,451	3,559	3,390	3,402
Non-impaired loans	189,334		197,423
Total loans	189,334		197,423
Commercial and Industrial [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for non-impaired loans	475		499
Total allowance for loan losses	475	476	499	569	401	416
Non-impaired loans	13,162		17,242
Total loans	13,162		17,242
Consumer [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for non-impaired loans	75		87
Total allowance for loan losses	75	76	87	105	105	127
Non-impaired loans	6,353		7,552
Total loans	6,353		7,552
One-to-Four Family [Member] \| Residential Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for impaired loans	89		81
Allowance for non-impaired loans	1,501		1,012
Total allowance for loan losses	1,590	1,236	1,093	1,272	1,522	1,646
Impaired loans	3,402		3,255
Non-impaired loans	351,520		233,109
Total loans	354,922		236,364
Second Mortgages and HELOC [Member] \| Residential Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for impaired loans	1		19
Allowance for non-impaired loans	510		443
Total allowance for loan losses	511	451	462	404	425	442
Impaired loans	580		603
Non-impaired loans	64,630		56,692
Total loans	65,210		57,295
Construction [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for non-impaired loans	727		697
Total allowance for loan losses	727	$ 716	697	$ 614	$ 720	$ 751
Non-impaired loans	33,877		33,961
Total loans	$ 33,877		$ 33,961