Allowance for Credit Losses - Changes in the Allowance for Credit Losses (Details) - USD ($) $ in Thousands	12 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2024
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	$ 46,191	$ 44,939	$ 48,734
Charge-offs	(2,530)	(1,136)	(10,276)
Recoveries	137	22	255
Provision for credit losses	1,698	2,366	6,226
Ending balance	45,496	46,191	44,939
Commercial Loan \| Multi-family mortgage
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	24,906	24,125	26,362
Charge-offs	(1,208)	0	(398)
Recoveries	0	0	0
Provision for credit losses	(1,137)	781	(1,839)
Ending balance	22,561	24,906	24,125
Commercial Loan \| Nonresidential mortgage
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	6,938	6,125	8,953
Charge-offs	(5)	(830)	(5,975)
Recoveries	0	0	120
Provision for credit losses	897	1,643	3,027
Ending balance	7,830	6,938	6,125
Commercial Loan \| Commercial and industrial
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	2,428	1,573	1,440
Charge-offs	(1,259)	(295)	(3,866)
Recoveries	118	20	22
Provision for credit losses	1,604	1,130	3,977
Ending balance	2,891	2,428	1,573
Commercial Loan \| Construction
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	1,155	1,230	1,336
Charge-offs	0	0	0
Recoveries	0	0	0
Provision for credit losses	695	(75)	(106)
Ending balance	1,850	1,155	1,230
One- to four-family residential mortgage
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	10,180	11,461	10,237
Charge-offs	(47)	(2)	(37)
Recoveries	19	2	113
Provision for credit losses	(568)	(1,281)	1,148
Ending balance	9,584	10,180	11,461
Consumer Loan \| Home equity loans
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	490	349	338
Charge-offs	(11)	(2)	0
Recoveries	0	0	0
Provision for credit losses	196	143	11
Ending balance	675	490	349
Consumer Loan \| Other consumer
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	94	76	68
Charge-offs	0	(7)	0
Recoveries	0	0	0
Provision for credit losses	11	25	8
Ending balance	$ 105	$ 94	$ 76

Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477657/942-210-S45-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478478/942-210-S50-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(7)(2))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1

Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479344/326-20-45-1

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Amount, excluding accrued interest, of increase in allowance for credit loss on financing receivable from recovery. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

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- Definition

Amount, excluding accrued interest, of decrease in allowance for credit loss on financing receivable from writeoff. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-6

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- Definition

Amount, excluding accrued interest, of credit loss expense (reversal of expense) on financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 22
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147476148/220-40-50-22

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