Loans Receivable - Troubled Debt Restructurings of Loans Receivable (Details) $ in Thousands	12 Months Ended
Jun. 30, 2023 USD ($) loan	Jun. 30, 2022 USD ($) loan
Financing Receivable Modifications [Line Items]
Number of Loans \| loan	62	68
Amount	$ 17,361	$ 22,184
Number of Loans \| loan	6	17
Pre-modification Recorded Investment	$ 1,130	$ 17,380
Post-modification Recorded Investment	$ 1,159	$ 17,474
Performing
Financing Receivable Modifications [Line Items]
Number of Loans \| loan	54	43
Amount	$ 10,487	$ 8,672
Nonperforming
Financing Receivable Modifications [Line Items]
Number of Loans \| loan	8	25
Amount	$ 6,874	$ 13,512
Commercial loans
Financing Receivable Modifications [Line Items]
Number of Loans \| loan	13	16
Amount	$ 9,467	$ 12,854
Commercial loans \| Performing
Financing Receivable Modifications [Line Items]
Number of Loans \| loan	9	9
Amount	$ 3,367	$ 4,020
Commercial loans \| Nonperforming
Financing Receivable Modifications [Line Items]
Number of Loans \| loan	4	7
Amount	$ 6,100	$ 8,834
Commercial loans \| Multi-family mortgage
Financing Receivable Modifications [Line Items]
Number of Loans \| loan	2	2
Amount	$ 5,400	$ 5,626
Number of Loans \| loan	0	2
Pre-modification Recorded Investment	$ 0	$ 12,091
Post-modification Recorded Investment	$ 0	$ 12,073
Commercial loans \| Multi-family mortgage \| Performing
Financing Receivable Modifications [Line Items]
Number of Loans \| loan	0	0
Amount	$ 0	$ 0
Commercial loans \| Multi-family mortgage \| Nonperforming
Financing Receivable Modifications [Line Items]
Number of Loans \| loan	2	2
Amount	$ 5,400	$ 5,626
Commercial loans \| Nonresidential mortgage
Financing Receivable Modifications [Line Items]
Number of Loans \| loan	5	6
Amount	$ 870	$ 1,954
Number of Loans \| loan	1	0
Pre-modification Recorded Investment	$ 313	$ 0
Post-modification Recorded Investment	$ 345	$ 0
Commercial loans \| Nonresidential mortgage \| Performing
Financing Receivable Modifications [Line Items]
Number of Loans \| loan	3	4
Amount	$ 170	$ 389
Commercial loans \| Nonresidential mortgage \| Nonperforming
Financing Receivable Modifications [Line Items]
Number of Loans \| loan	2	2
Amount	$ 700	$ 1,565
Commercial loans \| Commercial business
Financing Receivable Modifications [Line Items]
Number of Loans \| loan	6	7
Amount	$ 3,197	$ 3,713
Number of Loans \| loan	2	0
Pre-modification Recorded Investment	$ 74	$ 0
Post-modification Recorded Investment	$ 74	$ 0
Commercial loans \| Commercial business \| Performing
Financing Receivable Modifications [Line Items]
Number of Loans \| loan	6	5
Amount	$ 3,197	$ 3,631
Commercial loans \| Commercial business \| Nonperforming
Financing Receivable Modifications [Line Items]
Number of Loans \| loan	0	2
Amount	$ 0	$ 82
Commercial loans \| Construction
Financing Receivable Modifications [Line Items]
Number of Loans \| loan	0	1
Amount	$ 0	$ 1,561
Commercial loans \| Construction \| Performing
Financing Receivable Modifications [Line Items]
Number of Loans \| loan	0	0
Amount	$ 0	$ 0
Commercial loans \| Construction \| Nonperforming
Financing Receivable Modifications [Line Items]
Number of Loans \| loan	0	1
Amount	$ 0	$ 1,561
Residential mortgage
Financing Receivable Modifications [Line Items]
Number of Loans \| loan	43	45
Amount	$ 7,526	$ 7,802
Number of Loans \| loan	2	13
Pre-modification Recorded Investment	$ 708	$ 3,812
Post-modification Recorded Investment	$ 705	$ 3,924
Residential mortgage \| Performing
Financing Receivable Modifications [Line Items]
Number of Loans \| loan	39	29
Amount	$ 6,752	$ 4,488
Residential mortgage \| Nonperforming
Financing Receivable Modifications [Line Items]
Number of Loans \| loan	4	16
Amount	$ 774	$ 3,314
Consumer loans \| Home equity loans
Financing Receivable Modifications [Line Items]
Number of Loans \| loan	6	7
Amount	$ 368	$ 1,528
Number of Loans \| loan	1	2
Pre-modification Recorded Investment	$ 35	$ 1,477
Post-modification Recorded Investment	$ 35	$ 1,477
Consumer loans \| Home equity loans \| Performing
Financing Receivable Modifications [Line Items]
Number of Loans \| loan	6	5
Amount	$ 368	$ 164
Consumer loans \| Home equity loans \| Nonperforming
Financing Receivable Modifications [Line Items]
Number of Loans \| loan	0	2
Amount	$ 0	$ 1,364

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