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, 2026	Mar. 31, 2025	Mar. 31, 2026	Mar. 31, 2025	Jun. 30, 2025
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	$ 44,958	$ 44,457	$ 46,191	$ 44,939	$ 44,939
Charge-offs	(718)	(372)	(2,472)	(1,081)	(1,136)
Recoveries	92	4	128	16
Provision for (reversal of) credit losses	391	366	876	581
Ending balance	44,723	44,455	44,723	44,455	46,191
Commercial \| Multi-family mortgage
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	24,171	24,880	24,906	24,125	24,125
Charge-offs	(540)	0	(1,195)	0	0
Recoveries	0	0	0	0
Provision for (reversal of) credit losses	(581)	(220)	(661)	535
Ending balance	23,050	24,660	23,050	24,660	24,906
Commercial \| Nonresidential mortgage
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	7,871	6,479	6,938	6,125	6,125
Charge-offs	0	(332)	(5)	(830)	(830)
Recoveries	0	0	0	0
Provision for (reversal of) credit losses	(69)	529	869	1,381
Ending balance	7,802	6,676	7,802	6,676	6,938
Commercial \| Commercial business
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	1,984	1,563	2,428	1,573	1,573
Charge-offs	(178)	(40)	(1,214)	(242)	(295)
Recoveries	73	4	109	14
Provision for (reversal of) credit losses	739	(10)	1,295	172
Ending balance	2,618	1,517	2,618	1,517	2,428
Commercial \| Construction
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	1,284	1,157	1,155	1,230	1,230
Charge-offs	0	0	0	0	0
Recoveries	0	0	0	0
Provision for (reversal of) credit losses	153	(34)	282	(107)
Ending balance	1,437	1,123	1,437	1,123	1,155
Residential
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	9,075	9,855	10,180	11,461	11,461
Charge-offs	0	0	(47)	(2)	(2)
Recoveries	19	0	19	2
Provision for (reversal of) credit losses	123	103	(935)	(1,503)
Ending balance	9,217	9,958	9,217	9,958	10,180
Consumer \| Home equity loans
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	466	421	490	349	349
Charge-offs	0	0	(11)	(2)	(2)
Recoveries	0	0	0	0
Provision for (reversal of) credit losses	33	(4)	20	70
Ending balance	499	417	499	417	490
Consumer \| Other consumer
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	107	102	94	76	76
Charge-offs	0	0	0	(5)	(7)
Recoveries	0	0	0	0
Provision for (reversal of) credit losses	(7)	2	6	33
Ending balance	$ 100	$ 104	$ 100	$ 104	$ 94

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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+ 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 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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