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Loans and Allowance for Loan Losses, Major Loan Segments and Classes (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Sep. 30, 2021	Jun. 30, 2021	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020
Major Loan Segments and Classes [Abstract]
Total gross loans	$ 1,145,196		$ 1,108,408
Allowance for loan losses	(21,684)	$ (20,493)	(19,668)	$ (18,270)	$ (17,596)	$ (16,391)
Unearned origination fees and costs, net	(547)		(2,793)
Net loans receivable	1,122,965		1,085,947
Residential Real Estate [Member] \| Residential Real Estate [Member]
Major Loan Segments and Classes [Abstract]
Total gross loans	334,385		325,167
Allowance for loan losses	(1,981)	(1,997)	(2,012)	(1,998)	(1,463)	(2,091)
Residential Real Estate [Member] \| Construction and Land [Member]
Major Loan Segments and Classes [Abstract]
Total gross loans	13,884		10,185
Allowance for loan losses	(115)	(120)	(106)	(90)	(118)	(141)
Residential Real Estate [Member] \| Multi-family [Member]
Major Loan Segments and Classes [Abstract]
Total gross loans	44,450		41,951
Allowance for loan losses	(76)	(100)	(186)	(276)	(180)	(176)
Commercial Real Estate [Member] \| Real Estate [Member]
Major Loan Segments and Classes [Abstract]
Total gross loans	534,244		472,887
Allowance for loan losses	(15,616)	(14,298)	(13,049)	(10,207)	(9,384)	(8,634)
Commercial Real Estate [Member] \| Construction [Member]
Major Loan Segments and Classes [Abstract]
Total gross loans	75,417		62,763
Allowance for loan losses	(1,250)	(1,198)	(1,535)	(1,847)	(1,961)	(2,053)
Consumer Loan [Member] \| Home Equity [Member]
Major Loan Segments and Classes [Abstract]
Total gross loans	18,803		18,285
Allowance for loan losses	(89)	(140)	(165)	(265)	(272)	(295)
Consumer Loan [Member] \| Consumer Installment [Member]
Major Loan Segments and Classes [Abstract]
Total gross loans	4,669		4,942
Allowance for loan losses	(280)	(290)	(267)	(256)	(350)	(197)
Commercial Loans [Member]
Major Loan Segments and Classes [Abstract]
Total gross loans	119,344		172,228
Allowance for loan losses	$ (2,277)	$ (2,350)	$ (2,348)	$ (3,331)	$ (3,868)	$ (2,804)