Allowance for Credit Losses - Changes in the Allowance for Credit Losses (Details) - USD ($) $ in Thousands	12 Months Ended
Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2023
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	$ 44,939	$ 48,734	$ 47,058
Charge-offs	(1,136)	(10,276)	(896)
Recoveries	22	255	86
Provision for credit losses	2,366	6,226	2,486
Ending balance	46,191	44,939	48,734
Commercial Loan \| Multi-family mortgage
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	24,125	26,362	25,321
Charge-offs	0	(398)	(493)
Recoveries	0	0	0
Provision for credit losses	781	(1,839)	1,534
Ending balance	24,906	24,125	26,362
Commercial Loan \| Nonresidential mortgage
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	6,125	8,953	10,590
Charge-offs	(830)	(5,975)	(39)
Recoveries	0	120	0
Provision for credit losses	1,643	3,027	(1,598)
Ending balance	6,938	6,125	8,953
Commercial Loan \| Commercial business
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	1,573	1,440	1,792
Charge-offs	(295)	(3,866)	(364)
Recoveries	20	22	29
Provision for credit losses	1,130	3,977	(17)
Ending balance	2,428	1,573	1,440
Commercial Loan \| Construction
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	1,230	1,336	1,486
Charge-offs	0	0	0
Recoveries	0	0	0
Provision for credit losses	(75)	(106)	(150)
Ending balance	1,155	1,230	1,336
One- to four-family residential mortgage
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	11,461	10,237	7,540
Charge-offs	(2)	(37)	0
Recoveries	2	113	2
Provision for credit losses	(1,281)	1,148	2,695
Ending balance	10,180	11,461	10,237
Consumer Loan \| Home equity loans
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	349	338	245
Charge-offs	(2)	0	0
Recoveries	0	0	0
Provision for credit losses	143	11	93
Ending balance	490	349	338
Consumer Loan \| Other consumer
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	76	68	84
Charge-offs	(7)	0	0
Recoveries	0	0	55
Provision for credit losses	25	8	(71)
Ending balance	$ 94	$ 76	$ 68

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

Reference 1: 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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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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