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Loans and Allowance for Loan Losses, Major Loan Segments and Classes (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020	Jun. 30, 2020
Major Loan Segments and Classes [Abstract]
Total gross loans	$ 1,155,399		$ 1,108,408
Allowance for loan losses	(21,739)	$ (21,684)	(19,668)	$ (19,668)	$ (18,270)	$ (16,391)
Unearned origination fees and costs, net	(140)		(2,793)
Net loans receivable	1,133,520		1,085,947
Residential Real Estate [Member] \| Residential Real Estate [Member]
Major Loan Segments and Classes [Abstract]
Total gross loans	342,304		325,167
Allowance for loan losses	(2,006)	(1,981)	(2,012)	(1,985)	(1,998)	(2,091)
Residential Real Estate [Member] \| Construction and Land [Member]
Major Loan Segments and Classes [Abstract]
Total gross loans	14,054		10,185
Allowance for loan losses	(117)	(115)	(106)	(101)	(90)	(141)
Residential Real Estate [Member] \| Multi-family [Member]
Major Loan Segments and Classes [Abstract]
Total gross loans	51,100		41,951
Allowance for loan losses	(86)	(76)	(186)	(314)	(276)	(176)
Commercial Real Estate [Member] \| Real Estate [Member]
Major Loan Segments and Classes [Abstract]
Total gross loans	535,603		472,887
Allowance for loan losses	(15,892)	(15,616)	(13,049)	(11,779)	(10,207)	(8,634)
Commercial Real Estate [Member] \| Construction [Member]
Major Loan Segments and Classes [Abstract]
Total gross loans	77,303		62,763
Allowance for loan losses	(1,129)	(1,250)	(1,535)	(1,941)	(1,847)	(2,053)
Consumer Loan [Member] \| Home Equity [Member]
Major Loan Segments and Classes [Abstract]
Total gross loans	18,395		18,285
Allowance for loan losses	(87)	(89)	(165)	(201)	(265)	(295)
Consumer Loan [Member] \| Consumer Installment [Member]
Major Loan Segments and Classes [Abstract]
Total gross loans	4,365		4,942
Allowance for loan losses	(263)	(280)	(267)	(157)	(256)	(197)
Commercial Loans [Member]
Major Loan Segments and Classes [Abstract]
Total gross loans	112,275		172,228
Allowance for loan losses	$ (2,159)	$ (2,277)	$ (2,348)	$ (3,190)	$ (3,331)	$ (2,804)