Loans Receivable - Schedule of Loans Receivable (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Jun. 30, 2025
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying Value	$ 47,900
Financing receivable, before allowance for credit loss, fee and loan in process	5,878,562	$ 5,814,539
Unaccreted yield adjustments	(3,237)	(1,602)
Total loans receivable, net of yield adjustments	5,875,325	5,812,937
Nonperforming
Accounts, Notes, Loans and Financing Receivable [Line Items]
90 Days and Over Past Due Accruing	0	0
Nonaccrual Loans with Allowance for Credit Losses	13,743	20,847
Nonaccrual Loans with no Allowance for Credit Losses	34,153	24,750
Financing receivable, before allowance for credit loss, fee and loan in process	47,896	45,597
Performing
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, before allowance for credit loss, fee and loan in process	5,830,666	5,768,942
Collateral Pledged
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying Value	40,193	37,785
Related Allowance	1,054	1,377
Commercial Loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, before allowance for credit loss, fee and loan in process	4,006,466	4,012,678
Commercial Loan \| Collateral Pledged
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying Value	39,493	35,505
Related Allowance	1,054	1,377
Commercial Loan \| Multi-family mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, before allowance for credit loss, fee and loan in process	2,499,894	2,709,654
Commercial Loan \| Multi-family mortgage \| Nonperforming
Accounts, Notes, Loans and Financing Receivable [Line Items]
90 Days and Over Past Due Accruing	0	0
Nonaccrual Loans with Allowance for Credit Losses	10,617	15,867
Nonaccrual Loans with no Allowance for Credit Losses	26,263	14,990
Financing receivable, before allowance for credit loss, fee and loan in process	36,880	30,857
Commercial Loan \| Multi-family mortgage \| Performing
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, before allowance for credit loss, fee and loan in process	2,463,014	2,678,797
Commercial Loan \| Multi-family mortgage \| Collateral Pledged
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying Value	36,738	30,808
Related Allowance	1,054	1,377
Commercial Loan \| Nonresidential mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, before allowance for credit loss, fee and loan in process	1,019,445	986,556
Commercial Loan \| Nonresidential mortgage \| Nonperforming
Accounts, Notes, Loans and Financing Receivable [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	360	5,763
Financing receivable, before allowance for credit loss, fee and loan in process	360	5,763
Commercial Loan \| Nonresidential mortgage \| Performing
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, before allowance for credit loss, fee and loan in process	1,019,085	980,793
Commercial Loan \| Nonresidential mortgage \| Collateral Pledged
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying Value	0	4,697
Related Allowance	0	0
Commercial Loan \| Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, before allowance for credit loss, fee and loan in process	223,927	138,755
Commercial Loan \| Commercial and industrial \| Nonperforming
Accounts, Notes, Loans and Financing Receivable [Line Items]
90 Days and Over Past Due Accruing	0	0
Nonaccrual Loans with Allowance for Credit Losses	197	1,930
Nonaccrual Loans with no Allowance for Credit Losses	265	293
Financing receivable, before allowance for credit loss, fee and loan in process	462	2,223
Commercial Loan \| Commercial and industrial \| Performing
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, before allowance for credit loss, fee and loan in process	223,465	136,532
Commercial Loan \| Construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, before allowance for credit loss, fee and loan in process	263,200	177,713
Commercial Loan \| Construction \| Nonperforming
Accounts, Notes, Loans and Financing Receivable [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
Commercial Loan \| Construction \| Performing
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, before allowance for credit loss, fee and loan in process	260,445	177,713
Commercial Loan \| Construction \| Collateral Pledged
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying Value	2,755	0
Related Allowance	0	0
One- to four-family residential mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, before allowance for credit loss, fee and loan in process	1,789,865	1,748,591
One- to four-family residential mortgage \| Nonperforming
Accounts, Notes, Loans and Financing Receivable [Line Items]
90 Days and Over Past Due Accruing	0	0
Nonaccrual Loans with Allowance for Credit Losses	2,929	2,862
Nonaccrual Loans with no Allowance for Credit Losses	4,393	3,688
Financing receivable, before allowance for credit loss, fee and loan in process	7,322	6,550
One- to four-family residential mortgage \| Performing
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, before allowance for credit loss, fee and loan in process	1,782,543	1,742,041
One- to four-family residential mortgage \| Collateral Pledged
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying Value	687	2,264
Related Allowance	0	0
Consumer Loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, before allowance for credit loss, fee and loan in process	82,231	53,270
Consumer Loan \| Home equity loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, before allowance for credit loss, fee and loan in process	79,844	50,737
Consumer Loan \| Home equity loans \| Nonperforming
Accounts, Notes, Loans and Financing Receivable [Line Items]
90 Days and Over Past Due Accruing	0	0
Nonaccrual Loans with Allowance for Credit Losses	0	188
Nonaccrual Loans with no Allowance for Credit Losses	117	16
Financing receivable, before allowance for credit loss, fee and loan in process	117	204
Consumer Loan \| Home equity loans \| Performing
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, before allowance for credit loss, fee and loan in process	79,727	50,533
Consumer Loan \| Home equity loans \| Collateral Pledged
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying Value	13	16
Related Allowance	$ 0	$ 0

Financing Receivable, Nonaccrual, With Allowance

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Amount of allowance for credit loss on financing receivable evaluated on individual basis. Excludes financing receivable evaluated on collective basis.

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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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