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Allowance for Credit Losses - Allowance for Credit Losses and Balance of Loans Receivable (Details) - USD ($) $ in Thousands	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2022
Financing Receivable, Allowance for Credit Losses [Line Items]
Total allowance for credit losses	$ 46,191	$ 44,939	$ 48,734	$ 47,058
Loans individually analyzed	45,600
Total	5,814,539	5,748,750
Unaccreted yield adjustments	(1,602)	(15,963)
Total loans receivable, net of yield adjustments	5,812,937	5,732,787
Commercial business \| Multi-family mortgage
Financing Receivable, Allowance for Credit Losses [Line Items]
Total allowance for credit losses	24,906	24,125
Total	2,709,654	2,645,851
Commercial business \| Nonresidential mortgage
Financing Receivable, Allowance for Credit Losses [Line Items]
Total allowance for credit losses	6,938	6,125
Total	986,556	948,075
Commercial business \| Commercial business
Financing Receivable, Allowance for Credit Losses [Line Items]
Total allowance for credit losses	2,428	1,573
Total	138,755	142,747
Commercial business \| Construction
Financing Receivable, Allowance for Credit Losses [Line Items]
Total allowance for credit losses	1,155	1,230
Total	177,713	209,237
One- to four-family residential mortgage
Financing Receivable, Allowance for Credit Losses [Line Items]
Total allowance for credit losses	10,180	11,461	10,237	7,540
Total	1,748,591	1,756,051
Consumer Loan
Financing Receivable, Allowance for Credit Losses [Line Items]
Total	53,270	46,789
Consumer Loan \| Home equity loans
Financing Receivable, Allowance for Credit Losses [Line Items]
Total allowance for credit losses	490	349	338	245
Total	50,737	44,104
Consumer Loan \| Other consumer
Financing Receivable, Allowance for Credit Losses [Line Items]
Total allowance for credit losses	94	76	$ 68	$ 84
Total	2,533	2,685
Receivables Acquired with Deteriorated Credit Quality
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans individually analyzed	45	9
Loans collectively evaluated	130	132
Loans individually analyzed	875	1,584
Loans collectively evaluated	11,784	14,105
Receivables Acquired with Deteriorated Credit Quality \| Commercial business \| Multi-family mortgage
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans individually analyzed	0	0
Loans collectively evaluated	0	0
Loans individually analyzed	0	0
Loans collectively evaluated	0	0
Receivables Acquired with Deteriorated Credit Quality \| Commercial business \| Nonresidential mortgage
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans individually analyzed	0	0
Loans collectively evaluated	20	31
Loans individually analyzed	240	284
Loans collectively evaluated	1,405	2,145
Receivables Acquired with Deteriorated Credit Quality \| Commercial business \| Commercial business
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans individually analyzed	0	0
Loans collectively evaluated	23	6
Loans individually analyzed	0	0
Loans collectively evaluated	1,093	2,794
Receivables Acquired with Deteriorated Credit Quality \| Commercial business \| Construction
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans individually analyzed	0	0
Loans collectively evaluated	0	0
Loans individually analyzed	0	0
Loans collectively evaluated	5,735	5,735
Receivables Acquired with Deteriorated Credit Quality \| One- to four-family residential mortgage
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans individually analyzed	34	9
Loans collectively evaluated	87	95
Loans individually analyzed	614	1,276
Loans collectively evaluated	3,551	3,431
Receivables Acquired with Deteriorated Credit Quality \| Consumer Loan \| Home equity loans
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans individually analyzed	11	0
Loans collectively evaluated	0	0
Loans individually analyzed	21	24
Loans collectively evaluated	0	0
Receivables Acquired with Deteriorated Credit Quality \| Consumer Loan \| Other consumer
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans individually analyzed	0	0
Loans collectively evaluated	0	0
Loans individually analyzed	0	0
Loans collectively evaluated	0	0
Financial Asset, Other than Financial Asset Acquired with Credit Deterioration
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans individually analyzed	2,440	853
Loans collectively evaluated	43,576	43,945
Loans individually analyzed	44,722	38,293
Loans collectively evaluated	5,757,158	5,694,768
Financial Asset, Other than Financial Asset Acquired with Credit Deterioration \| Commercial business \| Multi-family mortgage
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans individually analyzed	1,377	0
Loans collectively evaluated	23,529	24,125
Loans individually analyzed	30,857	22,591
Loans collectively evaluated	2,678,797	2,623,260
Financial Asset, Other than Financial Asset Acquired with Credit Deterioration \| Commercial business \| Nonresidential mortgage
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans individually analyzed	0	517
Loans collectively evaluated	6,918	5,577
Loans individually analyzed	5,523	9,539
Loans collectively evaluated	979,388	936,107
Financial Asset, Other than Financial Asset Acquired with Credit Deterioration \| Commercial business \| Commercial business
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans individually analyzed	971	228
Loans collectively evaluated	1,434	1,339
Loans individually analyzed	2,223	714
Loans collectively evaluated	135,439	139,239
Financial Asset, Other than Financial Asset Acquired with Credit Deterioration \| Commercial business \| Construction
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans individually analyzed	0	0
Loans collectively evaluated	1,155	1,230
Loans individually analyzed	0	0
Loans collectively evaluated	171,978	203,502
Financial Asset, Other than Financial Asset Acquired with Credit Deterioration \| One- to four-family residential mortgage
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans individually analyzed	60	108
Loans collectively evaluated	9,999	11,249
Loans individually analyzed	5,936	5,429
Loans collectively evaluated	1,738,490	1,745,915
Financial Asset, Other than Financial Asset Acquired with Credit Deterioration \| Consumer Loan \| Home equity loans
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans individually analyzed	32	0
Loans collectively evaluated	447	349
Loans individually analyzed	183	20
Loans collectively evaluated	50,533	44,060
Financial Asset, Other than Financial Asset Acquired with Credit Deterioration \| Consumer Loan \| Other consumer
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans individually analyzed	0	0
Loans collectively evaluated	94	76
Loans individually analyzed	0	0
Loans collectively evaluated	$ 2,533	$ 2,685