Allowance for Credit Losses - Changes in the Allowance for Credit Losses (Details) - USD ($) $ in Thousands	12 Months Ended
Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2022
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	$ 48,734	$ 47,058	$ 58,165
Charge-offs	(10,276)	(896)	(4,737)
Recoveries	255	86	1,148
Initial allowance on PCD loans			0
Provision for (reversal of) credit losses	6,226	2,486	(7,518)
Ending balance	44,939	48,734	47,058
Impact of adopting Topic 326
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance			0
Commercial loans: \| Multi-family mortgage
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	26,362	25,321	28,450
Charge-offs	(398)	(493)	(1,896)
Recoveries	0	0	0
Initial allowance on PCD loans			0
Provision for (reversal of) credit losses	(1,839)	1,534	(1,233)
Ending balance	24,125	26,362	25,321
Commercial loans: \| Multi-family mortgage \| Impact of adopting Topic 326
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance			0
Commercial loans: \| Nonresidential mortgage
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	8,953	10,590	16,243
Charge-offs	(5,975)	(39)	(2,646)
Recoveries	120	0	812
Initial allowance on PCD loans			0
Provision for (reversal of) credit losses	3,027	(1,598)	(3,819)
Ending balance	6,125	8,953	10,590
Commercial loans: \| Nonresidential mortgage \| Impact of adopting Topic 326
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance			0
Commercial loans: \| Commercial business
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	1,440	1,792	2,086
Charge-offs	(3,866)	(364)	(193)
Recoveries	22	29	160
Initial allowance on PCD loans			0
Provision for (reversal of) credit losses	3,977	(17)	(261)
Ending balance	1,573	1,440	1,792
Commercial loans: \| Commercial business \| Impact of adopting Topic 326
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance			0
Commercial loans: \| Construction
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	1,336	1,486	1,170
Charge-offs	0	0	0
Recoveries	0	0	0
Initial allowance on PCD loans			0
Provision for (reversal of) credit losses	(106)	(150)	316
Ending balance	1,230	1,336	1,486
Commercial loans: \| Construction \| Impact of adopting Topic 326
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance			0
One- to four-family residential mortgage
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	10,237	7,540	9,747
Charge-offs	(37)	0	0
Recoveries	113	2	147
Initial allowance on PCD loans			0
Provision for (reversal of) credit losses	1,148	2,695	(2,354)
Ending balance	11,461	10,237	7,540
One- to four-family residential mortgage \| Impact of adopting Topic 326
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance			0
Consumer loans: \| Home equity loans
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	338	245	433
Charge-offs	0	0	0
Recoveries	0	0	27
Initial allowance on PCD loans			0
Provision for (reversal of) credit losses	11	93	(215)
Ending balance	349	338	245
Consumer loans: \| Home equity loans \| Impact of adopting Topic 326
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance			0
Consumer loans: \| Other consumer
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	68	84	36
Charge-offs	0	0	(2)
Recoveries	0	55	2
Initial allowance on PCD loans			0
Provision for (reversal of) credit losses	8	(71)	48
Ending balance	76	68	84
Consumer loans: \| Other consumer \| Impact of adopting Topic 326
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance			$ 0
Commercial business \| Multi-family mortgage
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	26,362
Charge-offs	(398)
Ending balance	24,125	26,362
Commercial business \| Nonresidential mortgage
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	8,953
Charge-offs	(5,975)
Ending balance	6,125	8,953
Commercial business \| Commercial business
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	1,440
Charge-offs	(3,866)
Ending balance	1,573	1,440
Commercial business \| Construction
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	1,336
Ending balance	$ 1,230	$ 1,336

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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- 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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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 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-6

Reference 2: 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

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- Definition

Amount, excluding accrued interest, of credit loss expense (reversal of expense) on financing receivable from change in methodology. 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 11
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-11

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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

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