ALLOWANCE FOR CREDIT LOSSES - Changes in the Allowance for Credit Losses (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
Mar. 31, 2025	Mar. 31, 2024	Mar. 31, 2025	Mar. 31, 2024	Jun. 30, 2024
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	$ 44,457	$ 44,867	$ 44,939	$ 48,734	$ 48,734
Charge-offs	(372)	(293)	(1,081)	(6,753)	(10,276)
Recoveries	4	7	16	250
Provision for (reversal of) credit losses	366	349	581	2,699
Ending balance	44,455	44,930	44,455	44,930	44,939
Commercial \| Multi-family mortgage
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	24,880	24,462	24,125	26,362	26,362
Charge-offs	0	(35)	0	(389)	(398)
Recoveries	0	0	0	0
Provision for (reversal of) credit losses	(220)	(231)	535	(1,777)
Ending balance	24,660	24,196	24,660	24,196	24,125
Commercial \| Nonresidential mortgage
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	6,479	5,888	6,125	8,953	8,953
Charge-offs	(332)	(253)	(830)	(5,975)	(5,975)
Recoveries	0	0	0	120
Provision for (reversal of) credit losses	529	415	1,381	2,952
Ending balance	6,676	6,050	6,676	6,050	6,125
Commercial \| Commercial business
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	1,563	1,293	1,573	1,440	1,440
Charge-offs	(40)	(5)	(242)	(352)	(3,866)
Recoveries	4	7	14	17
Provision for (reversal of) credit losses	(10)	250	172	440
Ending balance	1,517	1,545	1,517	1,545	1,573
Commercial \| Construction
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	1,157	1,171	1,230	1,336	1,336
Charge-offs	0	0	0	0	0
Recoveries	0	0	0	0
Provision for (reversal of) credit losses	(34)	179	(107)	14
Ending balance	1,123	1,350	1,123	1,350	1,230
Residential
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	9,855	11,653	11,461	10,237	10,237
Charge-offs	0	0	(2)	(37)	(37)
Recoveries	0	0	2	113
Provision for (reversal of) credit losses	103	(278)	(1,503)	1,062
Ending balance	9,958	11,375	9,958	11,375	11,461
Consumer \| Home equity loans
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	421	330	349	338	338
Charge-offs	0	0	(2)	0	0
Recoveries	0	0	0	0
Provision for (reversal of) credit losses	(4)	0	70	(8)
Ending balance	417	330	417	330	349
Consumer \| Other consumer
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	102	70	76	68	68
Charge-offs	0	0	(5)	0	0
Recoveries	0	0	0	0
Provision for (reversal of) credit losses	2	14	33	16
Ending balance	$ 104	$ 84	$ 104	$ 84	$ 76

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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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. 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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