Loans Receivable - Troubled Debt Restructurings of Loans Receivable (Details) - Troubled Debt Restructurings [Member] $ in Thousands	12 Months Ended
Jun. 30, 2022 USD ($) Loan	Jun. 30, 2021 USD ($) Loan
Financing Receivable Modifications [Line Items]
Number of Loans \| Loan	68	63
Number of Loans \| Loan	17	7
Amount	$ 22,184	$ 17,800
Pre-modification outstanding recorded investment	17,380	947
Post-modification outstanding recorded investment	$ 17,474	$ 951
One-to Four-Family Residential Mortgage [Member]
Financing Receivable Modifications [Line Items]
Number of Loans \| Loan	45	38
Number of Loans \| Loan	13	4
Amount	$ 7,802	$ 5,621
Pre-modification outstanding recorded investment	3,812	877
Post-modification outstanding recorded investment	$ 3,924	$ 881
Home Equity Loans [Member]
Financing Receivable Modifications [Line Items]
Number of Loans \| Loan	7	7
Number of Loans \| Loan	2	3
Amount	$ 1,528	$ 227
Pre-modification outstanding recorded investment	1,477	70
Post-modification outstanding recorded investment	$ 1,477	$ 70
Commercial Loan [Member]
Financing Receivable Modifications [Line Items]
Number of Loans \| Loan	16	18
Amount	$ 12,854	$ 11,952
Accrual [Member]
Financing Receivable Modifications [Line Items]
Number of Loans \| Loan	43	26
Amount	$ 8,672	$ 6,235
Accrual [Member] \| One-to Four-Family Residential Mortgage [Member]
Financing Receivable Modifications [Line Items]
Number of Loans \| Loan	29	18
Amount	$ 4,488	$ 2,216
Accrual [Member] \| Home Equity Loans [Member]
Financing Receivable Modifications [Line Items]
Number of Loans \| Loan	5	4
Amount	$ 164	$ 159
Accrual [Member] \| Commercial Loan [Member]
Financing Receivable Modifications [Line Items]
Number of Loans \| Loan	9	4
Amount	$ 4,020	$ 3,860
Non-accrual [Member]
Financing Receivable Modifications [Line Items]
Number of Loans \| Loan	25	37
Amount	$ 13,512	$ 11,565
Non-accrual [Member] \| One-to Four-Family Residential Mortgage [Member]
Financing Receivable Modifications [Line Items]
Number of Loans \| Loan	16	20
Amount	$ 3,314	$ 3,405
Non-accrual [Member] \| Home Equity Loans [Member]
Financing Receivable Modifications [Line Items]
Number of Loans \| Loan	2	3
Amount	$ 1,364	$ 68
Non-accrual [Member] \| Commercial Loan [Member]
Financing Receivable Modifications [Line Items]
Number of Loans \| Loan	7	14
Amount	$ 8,834	$ 8,092
Non-Residential Mortgage [Member] \| Commercial Loan [Member]
Financing Receivable Modifications [Line Items]
Number of Loans \| Loan	6	7
Amount	$ 1,954	$ 2,380
Non-Residential Mortgage [Member] \| Accrual [Member] \| Commercial Loan [Member]
Financing Receivable Modifications [Line Items]
Number of Loans \| Loan	4	1
Amount	$ 389	$ 105
Non-Residential Mortgage [Member] \| Non-accrual [Member] \| Commercial Loan [Member]
Financing Receivable Modifications [Line Items]
Number of Loans \| Loan	2	6
Amount	$ 1,565	$ 2,275
Commercial Business [Member] \| Commercial Loan [Member]
Financing Receivable Modifications [Line Items]
Number of Loans \| Loan	7	9
Amount	$ 3,713	$ 4,448
Commercial Business [Member] \| Accrual [Member] \| Commercial Loan [Member]
Financing Receivable Modifications [Line Items]
Number of Loans \| Loan	5	3
Amount	$ 3,631	$ 3,755
Commercial Business [Member] \| Non-accrual [Member] \| Commercial Loan [Member]
Financing Receivable Modifications [Line Items]
Number of Loans \| Loan	2	6
Amount	$ 82	$ 693
Construction [Member] \| Commercial Loan [Member]
Financing Receivable Modifications [Line Items]
Number of Loans \| Loan	1	1
Amount	$ 1,561	$ 2,228
Construction [Member] \| Accrual [Member] \| Commercial Loan [Member]
Financing Receivable Modifications [Line Items]
Number of Loans \| Loan	0
Construction [Member] \| Non-accrual [Member] \| Commercial Loan [Member]
Financing Receivable Modifications [Line Items]
Number of Loans \| Loan	1	1
Amount	$ 1,561	$ 2,228
Multi-Family Mortgage [Member]
Financing Receivable Modifications [Line Items]
Number of Loans \| Loan	2
Pre-modification outstanding recorded investment	$ 12,091
Post-modification outstanding recorded investment	$ 12,073
Multi-Family Mortgage [Member] \| Commercial Loan [Member]
Financing Receivable Modifications [Line Items]
Number of Loans \| Loan	2	1
Amount	$ 5,626	$ 2,896
Multi-Family Mortgage [Member] \| Non-accrual [Member] \| Commercial Loan [Member]
Financing Receivable Modifications [Line Items]
Number of Loans \| Loan	2	1
Amount	$ 5,626	$ 2,896

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
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