LOANS RECEIVABLE - Performance Status of Loans Receivable (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Jun. 30, 2025
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, before allowance for credit loss, fee and loan in process	$ 5,781,244	$ 5,814,539
Commercial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, before allowance for credit loss, fee and loan in process	3,976,465	4,012,678
Residential
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, before allowance for credit loss, fee and loan in process	1,741,023	1,748,591
Consumer
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, before allowance for credit loss, fee and loan in process	63,756	53,270
Nonperforming
Financing Receivable, Recorded Investment, Past Due [Line Items]
90 Days and Over Past Due Accruing	0	0
Nonaccrual Loans with Allowance for Credit Losses	10,323	20,847
Nonaccrual Loans with no Allowance for Credit Losses	42,056	24,750
Financing receivable, before allowance for credit loss, fee and loan in process	52,379	45,597
Nonperforming \| Residential
Financing Receivable, Recorded Investment, Past Due [Line Items]
90 Days and Over Past Due Accruing	0	0
Nonaccrual Loans with Allowance for Credit Losses	1,232	2,862
Nonaccrual Loans with no Allowance for Credit Losses	3,864	3,688
Financing receivable, before allowance for credit loss, fee and loan in process	5,096	6,550
Performing
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, before allowance for credit loss, fee and loan in process	5,728,865	5,768,942
Performing \| Residential
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, before allowance for credit loss, fee and loan in process	1,735,927	1,742,041
Multi-family mortgage \| Commercial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, before allowance for credit loss, fee and loan in process	2,555,001	2,709,654
Multi-family mortgage \| Nonperforming \| Commercial
Financing Receivable, Recorded Investment, Past Due [Line Items]
90 Days and Over Past Due Accruing	0	0
Nonaccrual Loans with Allowance for Credit Losses	8,802	15,867
Nonaccrual Loans with no Allowance for Credit Losses	29,314	14,990
Financing receivable, before allowance for credit loss, fee and loan in process	38,116	30,857
Multi-family mortgage \| Performing \| Commercial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, before allowance for credit loss, fee and loan in process	2,516,885	2,678,797
Nonresidential mortgage \| Commercial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, before allowance for credit loss, fee and loan in process	1,012,422	986,556
Nonresidential mortgage \| Nonperforming \| Commercial
Financing Receivable, Recorded Investment, Past Due [Line Items]
90 Days and Over Past Due Accruing	0	0
Nonaccrual Loans with Allowance for Credit Losses	0	0
Nonaccrual Loans with no Allowance for Credit Losses	5,679	5,763
Financing receivable, before allowance for credit loss, fee and loan in process	5,679	5,763
Nonresidential mortgage \| Performing \| Commercial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, before allowance for credit loss, fee and loan in process	1,006,743	980,793
Commercial business \| Commercial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, before allowance for credit loss, fee and loan in process	201,277	138,755
Commercial business \| Nonperforming \| Commercial
Financing Receivable, Recorded Investment, Past Due [Line Items]
90 Days and Over Past Due Accruing	0	0
Nonaccrual Loans with Allowance for Credit Losses	206	1,930
Nonaccrual Loans with no Allowance for Credit Losses	330	293
Financing receivable, before allowance for credit loss, fee and loan in process	536	2,223
Commercial business \| Performing \| Commercial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, before allowance for credit loss, fee and loan in process	200,741	136,532
Construction \| Commercial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, before allowance for credit loss, fee and loan in process	207,765	177,713
Construction \| Nonperforming \| Commercial
Financing Receivable, Recorded Investment, Past Due [Line Items]
90 Days and Over Past Due Accruing	0	0
Nonaccrual Loans with Allowance for Credit Losses	0	0
Nonaccrual Loans with no Allowance for Credit Losses	2,755	0
Financing receivable, before allowance for credit loss, fee and loan in process	2,755	0
Construction \| Performing \| Commercial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, before allowance for credit loss, fee and loan in process	205,010	177,713
Home equity loans \| Consumer
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, before allowance for credit loss, fee and loan in process	61,379	50,737
Home equity loans \| Nonperforming \| Consumer
Financing Receivable, Recorded Investment, Past Due [Line Items]
90 Days and Over Past Due Accruing	0	0
Nonaccrual Loans with Allowance for Credit Losses	83	188
Nonaccrual Loans with no Allowance for Credit Losses	114	16
Financing receivable, before allowance for credit loss, fee and loan in process	197	204
Home equity loans \| Performing \| Consumer
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, before allowance for credit loss, fee and loan in process	61,182	50,533
Other consumer \| Consumer
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, before allowance for credit loss, fee and loan in process	2,377	2,533
Other consumer \| Nonperforming \| Consumer
Financing Receivable, Recorded Investment, Past Due [Line Items]
90 Days and Over Past Due Accruing	0	0
Nonaccrual Loans with Allowance for Credit Losses	0	0
Nonaccrual Loans with no Allowance for Credit Losses	0	0
Financing receivable, before allowance for credit loss, fee and loan in process	0	0
Other consumer \| Performing \| Consumer
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, before allowance for credit loss, fee and loan in process	$ 2,377	$ 2,533

Financing Receivable, Nonaccrual, With Allowance

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- Definition

Amortized cost, before allowance for credit loss, fee, and loan in process, of financing receivable. Excludes financing receivable covered under loss sharing agreement and net investment in lease.

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Amortized cost excluding accrued interest, of financing receivable 90 days or more past due and still accruing. Excludes net investment in lease.

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Amortized cost of financing receivable on nonaccrual status with no allowance for credit loss. Excludes net investment in lease.

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- Definition

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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