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LOANS RECEIVABLE - Amortized Cost of Loans to Borrowers, Modified (Details) - USD ($) $ in Thousands	3 Months Ended
	Sep. 30, 2024	Sep. 30, 2023
Financing Receivable Modifications [Line Items]
Financing receivable, modified in period	$ 11,626	$ 534
Financing receivable, percent of total class	0.21%	0.03%
Payment Delay
Financing Receivable Modifications [Line Items]
Financing receivable, modified in period	$ 8,960	$ 534
Term Extension
Financing Receivable Modifications [Line Items]
Financing receivable, modified in period	0	0
Extended Maturity and Interest Rate Reduction
Financing Receivable Modifications [Line Items]
Financing receivable, modified in period	2,666
Commercial \| Multi-family mortgage
Financing Receivable Modifications [Line Items]
Financing receivable, modified in period	$ 11,448
Financing receivable, percent of total class	0.43%
Commercial \| Multi-family mortgage \| Payment Delay
Financing Receivable Modifications [Line Items]
Financing receivable, modified in period	$ 8,782
Commercial \| Multi-family mortgage \| Term Extension
Financing Receivable Modifications [Line Items]
Financing receivable, modified in period	0
Commercial \| Multi-family mortgage \| Extended Maturity and Interest Rate Reduction
Financing Receivable Modifications [Line Items]
Financing receivable, modified in period	2,666
Commercial \| Nonresidential mortgage
Financing Receivable Modifications [Line Items]
Financing receivable, modified in period	$ 178
Financing receivable, percent of total class	0.02%
Commercial \| Nonresidential mortgage \| Payment Delay
Financing Receivable Modifications [Line Items]
Financing receivable, modified in period	$ 178
Commercial \| Nonresidential mortgage \| Term Extension
Financing Receivable Modifications [Line Items]
Financing receivable, modified in period	0
Commercial \| Nonresidential mortgage \| Extended Maturity and Interest Rate Reduction
Financing Receivable Modifications [Line Items]
Financing receivable, modified in period	$ 0
Commercial \| Commercial business
Financing Receivable Modifications [Line Items]
Financing receivable, modified in period		$ 45
Financing receivable, percent of total class		0.03%
Commercial \| Commercial business \| Payment Delay
Financing Receivable Modifications [Line Items]
Financing receivable, modified in period		$ 45
Commercial \| Commercial business \| Term Extension
Financing Receivable Modifications [Line Items]
Financing receivable, modified in period		0
Commercial \| Home equity loans
Financing Receivable Modifications [Line Items]
Financing receivable, modified in period		$ 489
Financing receivable, percent of total class		0.03%
Commercial \| Home equity loans \| Payment Delay
Financing Receivable Modifications [Line Items]
Financing receivable, modified in period		$ 489
Commercial \| Home equity loans \| Term Extension
Financing Receivable Modifications [Line Items]
Financing receivable, modified in period		$ 0