ALLOWANCE FOR CREDIT LOSSES - Changes in the Allowance for Credit Losses (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2023	Dec. 31, 2022
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	$ 46,872	$ 47,613	$ 48,734	$ 47,058
Charge-offs	(4,238)	(415)	(6,460)	(543)
Recoveries	128	8	243	21
Provision for (reversal of) credit losses	2,105	1,671	2,350	2,341
Ending balance	44,867	48,877	44,867	48,877
Commercial \| Multi-family mortgage
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	25,590	26,246	26,362	25,321
Charge-offs	(354)	(395)	(354)	(395)
Recoveries	0	0	0	0
Provision for (reversal of) credit losses	(774)	1,647	(1,546)	2,572
Ending balance	24,462	27,498	24,462	27,498
Commercial \| Nonresidential mortgage
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	7,437	9,152	8,953	10,590
Charge-offs	(3,689)	(5)	(5,722)	(15)
Recoveries	11	0	120	0
Provision for (reversal of) credit losses	2,129	(554)	2,537	(1,982)
Ending balance	5,888	8,593	5,888	8,593
Commercial \| Commercial business
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	1,413	1,972	1,440	1,792
Charge-offs	(158)	(15)	(347)	(133)
Recoveries	4	5	10	17
Provision for (reversal of) credit losses	34	(143)	190	143
Ending balance	1,293	1,819	1,293	1,819
Commercial \| Construction
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	1,317	1,120	1,336	1,486
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision for (reversal of) credit losses	(146)	81	(165)	(285)
Ending balance	1,171	1,201	1,171	1,201
Residential
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	10,703	8,801	10,237	7,540
Charge-offs	(37)	0	(37)	0
Recoveries	113	0	113	0
Provision for (reversal of) credit losses	874	554	1,340	1,815
Ending balance	11,653	9,355	11,653	9,355
Consumer \| Home equity loans
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	342	244	338	245
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision for (reversal of) credit losses	(12)	95	(8)	94
Ending balance	330	339	330	339
Consumer \| Other consumer
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	70	78	68	84
Charge-offs	0	0	0	0
Recoveries	0	3	0	4
Provision for (reversal of) credit losses	0	(9)	2	(16)
Ending balance	$ 70	$ 72	$ 70	$ 72

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 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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