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Allowance for Credit Losses - Allowance for Credit Losses and Balance of Loans Receivable (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2023
Financing Receivable, Allowance for Credit Losses [Line Items]
Total allowance for credit losses	$ 45,496	$ 46,191	$ 44,939	$ 48,734
Loans individually analyzed	47,900
Total	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
Commercial business \| Multi-family mortgage
Financing Receivable, Allowance for Credit Losses [Line Items]
Total allowance for credit losses	22,561	24,906
Total	2,499,894	2,709,654
Commercial business \| Nonresidential mortgage
Financing Receivable, Allowance for Credit Losses [Line Items]
Total allowance for credit losses	7,830	6,938
Total	1,019,445	986,556
Commercial business \| Commercial and industrial
Financing Receivable, Allowance for Credit Losses [Line Items]
Total allowance for credit losses	2,891	2,428
Total	223,927	138,755
Commercial business \| Construction
Financing Receivable, Allowance for Credit Losses [Line Items]
Total allowance for credit losses	1,850	1,155
Total	263,200	177,713
One- to four-family residential mortgage
Financing Receivable, Allowance for Credit Losses [Line Items]
Total allowance for credit losses	9,584	10,180	11,461	10,237
Total	1,789,865	1,748,591
Consumer Loan
Financing Receivable, Allowance for Credit Losses [Line Items]
Total	82,231	53,270
Consumer Loan \| Home equity loans
Financing Receivable, Allowance for Credit Losses [Line Items]
Total allowance for credit losses	675	490	349	338
Total	79,844	50,737
Consumer Loan \| Other consumer
Financing Receivable, Allowance for Credit Losses [Line Items]
Total allowance for credit losses	105	94	$ 76	$ 68
Total	2,387	2,533
Receivables Acquired with Deteriorated Credit Quality
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans acquired with deteriorated credit quality individually analyzed	0	45
Loans collectively evaluated	73	130
Loans individually analyzed	1,020	875
Loans collectively evaluated	9,674	11,784
Receivables Acquired with Deteriorated Credit Quality \| Commercial business \| Multi-family mortgage
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans acquired with deteriorated credit quality 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 acquired with deteriorated credit quality individually analyzed	0	0
Loans collectively evaluated	13	20
Loans individually analyzed	203	240
Loans collectively evaluated	1,007	1,405
Receivables Acquired with Deteriorated Credit Quality \| Commercial business \| Commercial and industrial
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans acquired with deteriorated credit quality individually analyzed	0	0
Loans collectively evaluated	1	23
Loans individually analyzed	0	0
Loans collectively evaluated	94	1,093
Receivables Acquired with Deteriorated Credit Quality \| Commercial business \| Construction
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans acquired with deteriorated credit quality 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 acquired with deteriorated credit quality individually analyzed	0	34
Loans collectively evaluated	59	87
Loans individually analyzed	809	614
Loans collectively evaluated	2,838	3,551
Receivables Acquired with Deteriorated Credit Quality \| Consumer Loan \| Home equity loans
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans acquired with deteriorated credit quality individually analyzed	0	11
Loans collectively evaluated	0	0
Loans individually analyzed	8	21
Loans collectively evaluated	0	0
Receivables Acquired with Deteriorated Credit Quality \| Consumer Loan \| Other consumer
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans acquired with deteriorated credit quality 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 acquired with deteriorated credit quality individually analyzed	1,157	2,440
Loans collectively evaluated	44,266	43,576
Loans individually analyzed	46,876	44,722
Loans collectively evaluated	5,820,992	5,757,158
Financial Asset, Other than Financial Asset Acquired with Credit Deterioration \| Commercial business \| Multi-family mortgage
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans acquired with deteriorated credit quality individually analyzed	1,054	1,377
Loans collectively evaluated	21,507	23,529
Loans individually analyzed	36,880	30,857
Loans collectively evaluated	2,463,014	2,678,797
Financial Asset, Other than Financial Asset Acquired with Credit Deterioration \| Commercial business \| Nonresidential mortgage
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans acquired with deteriorated credit quality individually analyzed	0	0
Loans collectively evaluated	7,817	6,918
Loans individually analyzed	157	5,523
Loans collectively evaluated	1,018,078	979,388
Financial Asset, Other than Financial Asset Acquired with Credit Deterioration \| Commercial business \| Commercial and industrial
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans acquired with deteriorated credit quality individually analyzed	17	971
Loans collectively evaluated	2,873	1,434
Loans individually analyzed	462	2,223
Loans collectively evaluated	223,371	135,439
Financial Asset, Other than Financial Asset Acquired with Credit Deterioration \| Commercial business \| Construction
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans acquired with deteriorated credit quality individually analyzed	0	0
Loans collectively evaluated	1,850	1,155
Loans individually analyzed	2,755	0
Loans collectively evaluated	254,710	171,978
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 acquired with deteriorated credit quality individually analyzed	86	60
Loans collectively evaluated	9,439	9,999
Loans individually analyzed	6,513	5,936
Loans collectively evaluated	1,779,705	1,738,490
Financial Asset, Other than Financial Asset Acquired with Credit Deterioration \| Consumer Loan \| Home equity loans
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans acquired with deteriorated credit quality individually analyzed	0	32
Loans collectively evaluated	675	447
Loans individually analyzed	109	183
Loans collectively evaluated	79,727	50,533
Financial Asset, Other than Financial Asset Acquired with Credit Deterioration \| Consumer Loan \| Other consumer
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans acquired with deteriorated credit quality individually analyzed	0	0
Loans collectively evaluated	105	94
Loans individually analyzed	0	0
Loans collectively evaluated	$ 2,387	$ 2,533