Loans and Allowance for Loan Losses, Major Loan Segments and Classes (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Jun. 30, 2021	Sep. 30, 2020	Jun. 30, 2020
Major Loan Segments and Classes [Abstract]
Total gross loans	$ 1,118,784	$ 1,108,408
Allowance for loan losses	(20,493)	(19,668)	$ (17,596)	$ (16,391)
Unearned origination fees and costs, net	(1,475)	(2,793)
Net loans receivable	1,096,816	1,085,947
Residential Real Estate [Member] \| Residential Real Estate [Member]
Major Loan Segments and Classes [Abstract]
Total gross loans	326,274	325,167
Allowance for loan losses	(1,997)	(2,012)	(1,463)	(2,091)
Residential Real Estate [Member] \| Construction and Land [Member]
Major Loan Segments and Classes [Abstract]
Total gross loans	12,645	10,185
Allowance for loan losses	(120)	(106)	(118)	(141)
Residential Real Estate [Member] \| Multi-family [Member]
Major Loan Segments and Classes [Abstract]
Total gross loans	43,530	41,951
Allowance for loan losses	(100)	(186)	(180)	(176)
Commercial Real Estate [Member] \| Real Estate [Member]
Major Loan Segments and Classes [Abstract]
Total gross loans	511,117	472,887
Allowance for loan losses	(14,298)	(13,049)	(9,384)	(8,634)
Commercial Real Estate [Member] \| Construction [Member]
Major Loan Segments and Classes [Abstract]
Total gross loans	61,698	62,763
Allowance for loan losses	(1,198)	(1,535)	(1,961)	(2,053)
Consumer Loan [Member] \| Home Equity [Member]
Major Loan Segments and Classes [Abstract]
Total gross loans	18,736	18,285
Allowance for loan losses	(140)	(165)	(272)	(295)
Consumer Loan [Member] \| Consumer Installment [Member]
Major Loan Segments and Classes [Abstract]
Total gross loans	4,897	4,942
Allowance for loan losses	(290)	(267)	(350)	(197)
Commercial Loans [Member]
Major Loan Segments and Classes [Abstract]
Total gross loans	139,887	172,228
Allowance for loan losses	$ (2,350)	$ (2,348)	$ (3,868)	$ (2,804)

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

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Amount, before allowance for credit loss, of financing receivable.

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