Loans and Allowance for Loan Losses - Schedule of Past Due and Non-Accrual Loans (Detail) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	$ 1,273	$ 1,380
Non-accrual Loans	2,681	2,624
Consumer [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	15	85
One-to-Four Family [Member] | Residential Real Estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	888	894
Non-accrual Loans	2,299	2,133
Home Equity Loans and Lines of Credit [Member] | Residential Real Estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	370	401
Non-accrual Loans	382	491
30 - 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	852	963
30 - 59 Days Past Due [Member] | Consumer [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	15	76
30 - 59 Days Past Due [Member] | One-to-Four Family [Member] | Residential Real Estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	665	701
30 - 59 Days Past Due [Member] | Home Equity Loans and Lines of Credit [Member] | Residential Real Estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	172	186
60 - 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	421	417
60 - 89 Days Past Due [Member] | Consumer [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due		9
60 - 89 Days Past Due [Member] | One-to-Four Family [Member] | Residential Real Estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	223	193
60 - 89 Days Past Due [Member] | Home Equity Loans and Lines of Credit [Member] | Residential Real Estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	$ 198	$ 215