Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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LOANS RECEIVABLE - Schedule of Loans Receivable (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Mar. 31, 2025	Mar. 31, 2024	Mar. 31, 2025	Mar. 31, 2024	Jun. 30, 2024
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, before allowance for credit loss, fee and loan in process	$ 5,850,449		$ 5,850,449		$ 5,748,750
Unaccreted yield adjustments	(4,274)		(4,274)		(15,963)
Loans receivable	5,846,175		5,846,175		5,732,787
Originated more than five years before current fiscal year, writeoff			1,081		6,421
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff	372	$ 293	1,081	$ 6,753	10,276
Originated current fiscal year, writeoff			0		0
Originated fiscal year before current fiscal year, writeoff			0		0
Originated two years before current fiscal year, writeoff			0		0
Originated three years before current fiscal year, writeoff			0		3,391
Originated four years before current fiscal year, writeoff			0		464
Revolving loans, writeoff			0		0
Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, before allowance for credit loss, fee and loan in process	4,036,426		4,036,426		3,945,910
Commercial \| Multi-family mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, before allowance for credit loss, fee and loan in process	2,733,406		2,733,406		2,645,851
Originated more than five years before current fiscal year, writeoff			0		398
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff	0	35	0	389	398
Originated current fiscal year, writeoff			0		0
Originated fiscal year before current fiscal year, writeoff			0		0
Originated two years before current fiscal year, writeoff			0		0
Originated three years before current fiscal year, writeoff			0		0
Originated four years before current fiscal year, writeoff			0		0
Revolving loans, writeoff			0		0
Commercial \| Nonresidential mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, before allowance for credit loss, fee and loan in process	988,074		988,074		948,075
Originated more than five years before current fiscal year, writeoff			830		5,975
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff	332	253	830	5,975	5,975
Originated current fiscal year, writeoff			0
Originated fiscal year before current fiscal year, writeoff			0
Originated two years before current fiscal year, writeoff			0
Originated three years before current fiscal year, writeoff			0
Originated four years before current fiscal year, writeoff			0
Revolving loans, writeoff			0
Commercial \| Commercial business
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, before allowance for credit loss, fee and loan in process	140,224		140,224		142,747
Originated more than five years before current fiscal year, writeoff			242		11
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff	40	5	242	352	3,866
Originated current fiscal year, writeoff			0		0
Originated fiscal year before current fiscal year, writeoff			0		0
Originated two years before current fiscal year, writeoff			0		0
Originated three years before current fiscal year, writeoff			0		3,391
Originated four years before current fiscal year, writeoff			0		464
Revolving loans, writeoff			0		0
Commercial \| Construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, before allowance for credit loss, fee and loan in process	174,722		174,722		209,237
Originated more than five years before current fiscal year, writeoff			0		0
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff	0	0	0	0	0
Originated current fiscal year, writeoff			0		0
Originated fiscal year before current fiscal year, writeoff			0		0
Originated two years before current fiscal year, writeoff			0		0
Originated three years before current fiscal year, writeoff			0		0
Originated four years before current fiscal year, writeoff			0		0
Revolving loans, writeoff			0		0
Residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, before allowance for credit loss, fee and loan in process	1,761,465		1,761,465		1,756,051
Originated more than five years before current fiscal year, writeoff			2		37
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff	0	0	2	37	37
Originated current fiscal year, writeoff			0		0
Originated fiscal year before current fiscal year, writeoff			0		0
Originated two years before current fiscal year, writeoff			0		0
Originated three years before current fiscal year, writeoff			0		0
Originated four years before current fiscal year, writeoff			0		0
Revolving loans, writeoff			0		0
Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, before allowance for credit loss, fee and loan in process	52,558		52,558		46,789
Consumer \| Home equity loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, before allowance for credit loss, fee and loan in process	49,699		49,699		44,104
Originated more than five years before current fiscal year, writeoff			2		0
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff	0	0	2	0	0
Originated current fiscal year, writeoff			0		0
Originated fiscal year before current fiscal year, writeoff			0		0
Originated two years before current fiscal year, writeoff			0		0
Originated three years before current fiscal year, writeoff			0		0
Originated four years before current fiscal year, writeoff			0		0
Revolving loans, writeoff			0		0
Consumer \| Other consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, before allowance for credit loss, fee and loan in process	2,859		2,859		2,685
Originated more than five years before current fiscal year, writeoff			5		0
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff	$ 0	$ 0	5	$ 0	0
Originated current fiscal year, writeoff			0		0
Originated fiscal year before current fiscal year, writeoff			0		0
Originated two years before current fiscal year, writeoff			0		0
Originated three years before current fiscal year, writeoff			0		0
Originated four years before current fiscal year, writeoff			0		0
Revolving loans, writeoff			$ 0		$ 0