Loans Receivable - Performance Status of Loans Receivable (Details) - USD ($) $ in Thousands	Jun. 30, 2025	Jun. 30, 2024
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, before allowance for credit loss, fee and loan in process	$ 5,814,539	$ 5,748,750
Commercial Loan
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, before allowance for credit loss, fee and loan in process	4,012,678	3,945,910
One- to four-family residential mortgage
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, before allowance for credit loss, fee and loan in process	1,748,591	1,756,051
Consumer Loan
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, before allowance for credit loss, fee and loan in process	53,270	46,789
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	20,847	8,704
Nonaccrual Loans with no Allowance for Credit Losses	24,750	31,178
Financing receivable, before allowance for credit loss, fee and loan in process	45,597	39,882
Nonperforming \| One- to four-family residential mortgage
Financing Receivable, Recorded Investment, Past Due [Line Items]
90 Days and Over Past Due Accruing	0	0
Nonaccrual Loans with Allowance for Credit Losses	2,862	2,295
Nonaccrual Loans with no Allowance for Credit Losses	3,688	4,410
Financing receivable, before allowance for credit loss, fee and loan in process	6,550	6,705
Performing
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, before allowance for credit loss, fee and loan in process	5,768,942	5,708,868
Performing \| One- to four-family residential mortgage
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, before allowance for credit loss, fee and loan in process	1,742,041	1,749,346
Multi-family mortgage \| Commercial Loan
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, before allowance for credit loss, fee and loan in process	2,709,654	2,645,851
Multi-family mortgage \| Nonperforming \| Commercial Loan
Financing Receivable, Recorded Investment, Past Due [Line Items]
90 Days and Over Past Due Accruing	0	0
Nonaccrual Loans with Allowance for Credit Losses	15,867	0
Nonaccrual Loans with no Allowance for Credit Losses	14,990	22,591
Financing receivable, before allowance for credit loss, fee and loan in process	30,857	22,591
Multi-family mortgage \| Performing \| Commercial Loan
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, before allowance for credit loss, fee and loan in process	2,678,797	2,623,260
Nonresidential mortgage \| Commercial Loan
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, before allowance for credit loss, fee and loan in process	986,556	948,075
Nonresidential mortgage \| Nonperforming \| Commercial Loan
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	5,695
Nonaccrual Loans with no Allowance for Credit Losses	5,763	4,128
Financing receivable, before allowance for credit loss, fee and loan in process	5,763	9,823
Nonresidential mortgage \| Performing \| Commercial Loan
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, before allowance for credit loss, fee and loan in process	980,793	938,252
Commercial business \| Commercial Loan
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, before allowance for credit loss, fee and loan in process	138,755	142,747
Commercial business \| Nonperforming \| Commercial Loan
Financing Receivable, Recorded Investment, Past Due [Line Items]
90 Days and Over Past Due Accruing	0	0
Nonaccrual Loans with Allowance for Credit Losses	1,930	714
Nonaccrual Loans with no Allowance for Credit Losses	293	0
Financing receivable, before allowance for credit loss, fee and loan in process	2,223	714
Commercial business \| Performing \| Commercial Loan
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, before allowance for credit loss, fee and loan in process	136,532	142,033
Construction \| Commercial Loan
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, before allowance for credit loss, fee and loan in process	177,713	209,237
Construction \| Nonperforming \| Commercial Loan
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
Construction \| Performing \| Commercial Loan
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, before allowance for credit loss, fee and loan in process	177,713	209,237
Home equity loans \| Consumer Loan
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, before allowance for credit loss, fee and loan in process	50,737	44,104
Home equity loans \| Nonperforming \| Consumer Loan
Financing Receivable, Recorded Investment, Past Due [Line Items]
90 Days and Over Past Due Accruing	0	0
Nonaccrual Loans with Allowance for Credit Losses	188	0
Nonaccrual Loans with no Allowance for Credit Losses	16	44
Financing receivable, before allowance for credit loss, fee and loan in process	204	44
Home equity loans \| Performing \| Consumer Loan
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, before allowance for credit loss, fee and loan in process	50,533	44,060
Other consumer \| Consumer Loan
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, before allowance for credit loss, fee and loan in process	2,533	2,685
Other consumer \| Nonperforming \| Consumer Loan
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	5
Financing receivable, before allowance for credit loss, fee and loan in process	0	5
Other consumer \| Performing \| Consumer Loan
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, before allowance for credit loss, fee and loan in process	$ 2,533	$ 2,680

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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