Loans, Allowance for Credit Losses and Credit Quality - Schedule of Loans (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Jun. 30, 2023	Dec. 31, 2022	Sep. 30, 2022	Jun. 30, 2022	Dec. 31, 2021
Accounts Notes And Loans Receivable [Line Items]
Total loans, gross	$ 1,005,880		$ 893,132
Net deferred loan fees	(229)		(258)
Allowance for credit losses	(8,292)		(7,200)	$ (6,037)	$ (5,111)	$ (4,236)
Total loans, net	$ 997,359		$ 885,674
Total loans, gross percent	100.00%		100.00%
Real Estate Loans | Home Equity Lines of Credit and Loans
Accounts Notes And Loans Receivable [Line Items]
Total loans, gross	$ 33,407		$ 27,783
Allowance for credit losses	$ (207)	$ (203)	$ (194)	(204)	(193)	(185)
Total loans, gross percent	3.30%		3.10%
Real Estate Loans | One-to Four Family Residential
Accounts Notes And Loans Receivable [Line Items]
Total loans, gross	$ 395,290		$ 355,381
Total loans, gross percent	39.30%		39.80%
Real Estate Loans | Multi Family
Accounts Notes And Loans Receivable [Line Items]
Total loans, gross	$ 281,192		$ 241,951
Allowance for credit losses	$ (2,229)	(2,150)	$ (1,839)	(1,165)	(779)	(417)
Total loans, gross percent	28.00%		27.10%
Real Estate Loans | Commercial Real Estate Loans
Accounts Notes And Loans Receivable [Line Items]
Total loans, gross	$ 185,657		$ 156,212
Allowance for credit losses	$ (2,194)	(2,348)	$ (1,797)	(1,554)	(1,353)	(1,099)
Total loans, gross percent	18.50%		17.50%
Real Estate Loans | Construction
Accounts Notes And Loans Receivable [Line Items]
Total loans, gross	$ 101,615		$ 107,317
Allowance for credit losses	$ (1,444)	(1,570)	$ (1,286)	(1,081)	(950)	(855)
Total loans, gross percent	10.10%		12.00%
Other Loans | Commercial Loans
Accounts Notes And Loans Receivable [Line Items]
Total loans, gross	$ 8,471		$ 4,266
Allowance for credit losses	$ (197)	(218)	$ (60)	(60)	(46)	(60)
Total loans, gross percent	0.80%		0.50%
Other Loans | Consumer
Accounts Notes And Loans Receivable [Line Items]
Total loans, gross	$ 248		$ 222
Allowance for credit losses	$ (1)	$ (1)	$ (1)	$ (1)	$ (1)	$ (2)
Total loans, gross percent	0.00%		0.00%