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, 2026	Mar. 31, 2025	Mar. 31, 2026	Mar. 31, 2025	Jun. 30, 2025
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, before allowance for credit loss, fee and loan in process	$ 5,781,244		$ 5,781,244		$ 5,814,539
Unaccreted yield adjustments	(2,063)		(2,063)		(1,602)
Loans receivable	5,779,181		5,779,181		5,812,937
Originated more than five years before current fiscal year, charge-offs			2,072		1,136
Originated current fiscal year, charge-offs			0		0
Originated fiscal year before current fiscal year, charge-offs			0		0
Originated two years before current fiscal year, charge-offs			400		0
Originated three years before current fiscal year, charge-offs			0		0
Total period writeoff	718	$ 372	2,472	$ 1,081	1,136
Originated four years before current fiscal year, charge-offs			0		0
Revolving loans, charge-offs			0		0
Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, before allowance for credit loss, fee and loan in process	3,976,465		3,976,465		4,012,678
Commercial \| Multi-family mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, before allowance for credit loss, fee and loan in process	2,555,001		2,555,001		2,709,654
Originated more than five years before current fiscal year, charge-offs			1,195		0
Originated current fiscal year, charge-offs			0		0
Originated fiscal year before current fiscal year, charge-offs			0		0
Originated two years before current fiscal year, charge-offs			0		0
Originated three years before current fiscal year, charge-offs			0		0
Total period writeoff	540	0	1,195	0	0
Originated four years before current fiscal year, charge-offs			0		0
Revolving loans, charge-offs			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	1,012,422		1,012,422		986,556
Originated more than five years before current fiscal year, charge-offs			5		830
Originated current fiscal year, charge-offs			0
Originated fiscal year before current fiscal year, charge-offs			0
Originated two years before current fiscal year, charge-offs			0
Originated three years before current fiscal year, charge-offs			0
Total period writeoff	0	332	5	830	830
Originated four years before current fiscal year, charge-offs			0
Revolving loans, charge-offs			0
Commercial \| Commercial business
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, before allowance for credit loss, fee and loan in process	201,277		201,277		138,755
Originated more than five years before current fiscal year, charge-offs			814		295
Originated current fiscal year, charge-offs			0		0
Originated fiscal year before current fiscal year, charge-offs			0		0
Originated two years before current fiscal year, charge-offs			400		0
Originated three years before current fiscal year, charge-offs			0		0
Total period writeoff	178	40	1,214	242	295
Originated four years before current fiscal year, charge-offs			0		0
Revolving loans, charge-offs			0		0
Commercial \| Construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, before allowance for credit loss, fee and loan in process	207,765		207,765		177,713
Originated more than five years before current fiscal year, charge-offs			0		0
Originated current fiscal year, charge-offs			0		0
Originated fiscal year before current fiscal year, charge-offs			0		0
Originated two years before current fiscal year, charge-offs			0		0
Originated three years before current fiscal year, charge-offs			0		0
Total period writeoff	0	0	0	0	0
Originated four years before current fiscal year, charge-offs			0		0
Revolving loans, charge-offs			0		0
Residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, before allowance for credit loss, fee and loan in process	1,741,023		1,741,023		1,748,591
Originated more than five years before current fiscal year, charge-offs			47		2
Originated current fiscal year, charge-offs			0		0
Originated fiscal year before current fiscal year, charge-offs			0		0
Originated two years before current fiscal year, charge-offs			0		0
Originated three years before current fiscal year, charge-offs			0		0
Total period writeoff	0	0	47	2	2
Originated four years before current fiscal year, charge-offs			0		0
Revolving loans, charge-offs			0		0
Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, before allowance for credit loss, fee and loan in process	63,756		63,756		53,270
Consumer \| Home equity loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, before allowance for credit loss, fee and loan in process	61,379		61,379		50,737
Originated more than five years before current fiscal year, charge-offs			11		2
Originated current fiscal year, charge-offs			0		0
Originated fiscal year before current fiscal year, charge-offs			0		0
Originated two years before current fiscal year, charge-offs			0		0
Originated three years before current fiscal year, charge-offs			0		0
Total period writeoff	0	0	11	2	2
Originated four years before current fiscal year, charge-offs			0		0
Revolving loans, charge-offs			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	2,377		2,377		2,533
Originated more than five years before current fiscal year, charge-offs			0		7
Originated current fiscal year, charge-offs			0		0
Originated fiscal year before current fiscal year, charge-offs			0		0
Originated two years before current fiscal year, charge-offs			0		0
Originated three years before current fiscal year, charge-offs			0		0
Total period writeoff	$ 0	$ 0	0	$ 5	7
Originated four years before current fiscal year, charge-offs			0		0
Revolving loans, charge-offs			$ 0		$ 0