Loans and Allowance for Credit Losses - Balance and activity in the Allowance for credit losses (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
Mar. 31, 2024	Mar. 31, 2023	Mar. 31, 2024	Mar. 31, 2023	Jun. 30, 2023
Allowance for credit losses:
Balance, beginning of period	$ 50,084	$ 37,483	$ 47,820	$ 33,192	$ 33,192
Provision (benefit) charged to expense	1,358	7,185	4,850	11,800
Losses charged off	(114)	(113)	(1,430)	(453)
Recoveries	8	9	96	25
Balance, end of period	51,336	45,685	51,336	45,685	47,820
Impact of adoption ASU
Allowance for credit losses:
Initial ACL on PCD loans		1,121		1,121
Residential Real Estate
Allowance for credit losses:
Balance, beginning of period	15,096	12,499	15,641	8,908	8,908
Provision (benefit) charged to expense	262	870	(151)	4,462
Losses charged off	(1)		(133)	(2)
Recoveries				1
Balance, end of period	15,357	13,465	15,357	13,465	15,641
Residential Real Estate \| Impact of adoption ASU
Allowance for credit losses:
Initial ACL on PCD loans		96		96
Construction Real Estate
Allowance for credit losses:
Balance, beginning of period	2,864	2,754	2,664	2,220	2,220
Provision (benefit) charged to expense	(517)	872	(28)	1,406
Losses charged off			(289)
Balance, end of period	2,347	3,638	2,347	3,638	2,664
Construction Real Estate \| Impact of adoption ASU
Allowance for credit losses:
Initial ACL on PCD loans		12		12
Commercial Real Estate
Allowance for credit losses:
Balance, beginning of period	25,177	16,806	22,838	16,838	16,838
Provision (benefit) charged to expense	1,433	1,111	4,250	1,324
Losses charged off			(496)	(245)
Recoveries			18
Balance, end of period	26,610	18,545	26,610	18,545	22,838
Commercial Real Estate \| Impact of adoption ASU
Allowance for credit losses:
Initial ACL on PCD loans		628		628
Consumer loans
Allowance for credit losses:
Balance, beginning of period	890	761	909	710	710
Provision (benefit) charged to expense	53	165	185	283
Losses charged off	(48)	(113)	(263)	(189)
Recoveries	5	9	69	18
Balance, end of period	900	986	900	986	909
Consumer loans \| Impact of adoption ASU
Allowance for credit losses:
Initial ACL on PCD loans		164		164
Commercial loans
Allowance for credit losses:
Balance, beginning of period	6,057	4,663	5,768	4,516	4,516
Provision (benefit) charged to expense	127	4,167	594	4,325
Losses charged off	(65)		(249)	(17)
Recoveries	3		9	6
Balance, end of period	$ 6,122	9,051	$ 6,122	9,051	$ 5,768
Commercial loans \| Impact of adoption ASU
Allowance for credit losses:
Initial ACL on PCD loans		$ 221		$ 221

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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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
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-13

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+ 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
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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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Amount, excluding accrued interest, of allowance for credit loss at acquisition date of financing receivable purchased with credit deterioration. 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 19
-Subparagraph (b)
-Publisher FASB
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