LOANS RECEIVABLE - Troubled Debt Restructurings of Loans Receivable (Details) $ in Thousands	3 Months Ended
Sep. 30, 2022 USD ($) loan	Jun. 30, 2023 USD ($) loan
Financing Receivable Modifications [Line Items]
Number of TDR defaults \| loan		62
Amount		$ 17,361
Number of TDR defaults \| loan	2
Pre- modification Recorded Investment	$ 470
Post- modification Recorded Investment	$ 470
Accrual
Financing Receivable Modifications [Line Items]
Number of TDR defaults \| loan		54
Amount		$ 10,487
Non-accrual
Financing Receivable Modifications [Line Items]
Number of TDR defaults \| loan		8
Amount		$ 6,874
Commercial
Financing Receivable Modifications [Line Items]
Number of TDR defaults \| loan		13
Amount		$ 9,467
Commercial \| Accrual
Financing Receivable Modifications [Line Items]
Number of TDR defaults \| loan		9
Amount		$ 3,367
Commercial \| Non-accrual
Financing Receivable Modifications [Line Items]
Number of TDR defaults \| loan		4
Amount		$ 6,100
Commercial \| Multi-family mortgage
Financing Receivable Modifications [Line Items]
Number of TDR defaults \| loan		2
Amount		$ 5,400
Commercial \| Multi-family mortgage \| Accrual
Financing Receivable Modifications [Line Items]
Number of TDR defaults \| loan		0
Amount		$ 0
Commercial \| Multi-family mortgage \| Non-accrual
Financing Receivable Modifications [Line Items]
Number of TDR defaults \| loan		2
Amount		$ 5,400
Commercial \| Nonresidential mortgage
Financing Receivable Modifications [Line Items]
Number of TDR defaults \| loan		5
Amount		$ 870
Commercial \| Nonresidential mortgage \| Accrual
Financing Receivable Modifications [Line Items]
Number of TDR defaults \| loan		3
Amount		$ 170
Commercial \| Nonresidential mortgage \| Non-accrual
Financing Receivable Modifications [Line Items]
Number of TDR defaults \| loan		2
Amount		$ 700
Commercial \| Commercial business
Financing Receivable Modifications [Line Items]
Number of TDR defaults \| loan		6
Amount		$ 3,197
Commercial \| Commercial business \| Accrual
Financing Receivable Modifications [Line Items]
Number of TDR defaults \| loan		6
Amount		$ 3,197
Commercial \| Commercial business \| Non-accrual
Financing Receivable Modifications [Line Items]
Number of TDR defaults \| loan		0
Amount		$ 0
Commercial \| Construction
Financing Receivable Modifications [Line Items]
Number of TDR defaults \| loan		0
Amount		$ 0
Commercial \| Construction \| Accrual
Financing Receivable Modifications [Line Items]
Number of TDR defaults \| loan		0
Amount		$ 0
Commercial \| Construction \| Non-accrual
Financing Receivable Modifications [Line Items]
Number of TDR defaults \| loan		0
Amount		$ 0
Residential
Financing Receivable Modifications [Line Items]
Number of TDR defaults \| loan		43
Amount		$ 7,526
Number of TDR defaults \| loan	1
Pre- modification Recorded Investment	$ 435
Post- modification Recorded Investment	$ 435
Residential \| Accrual
Financing Receivable Modifications [Line Items]
Number of TDR defaults \| loan		39
Amount		$ 6,752
Residential \| Non-accrual
Financing Receivable Modifications [Line Items]
Number of TDR defaults \| loan		4
Amount		$ 774
Consumer \| Home equity loans
Financing Receivable Modifications [Line Items]
Number of TDR defaults \| loan		6
Amount		$ 368
Number of TDR defaults \| loan	1
Pre- modification Recorded Investment	$ 35
Post- modification Recorded Investment	$ 35
Consumer \| Home equity loans \| Accrual
Financing Receivable Modifications [Line Items]
Number of TDR defaults \| loan		6
Amount		$ 368
Consumer \| Home equity loans \| Non-accrual
Financing Receivable Modifications [Line Items]
Number of TDR defaults \| loan		0
Amount		$ 0

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