Loans and Allowance for Credit Losses - Allowance for off-balance credit exposure (Details) - USD ($) $ in Thousands	12 Months Ended
Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2021
Allowance for off-balance sheet credit exposure:
Balance, beginning of period	$ 3,358	$ 1,805	$ 1,959
Provision (benefit) charged to expense	2,930	1,553	(422)
Balance, end of period	6,288	3,358	1,805
Accounting Standards Update 2016-13
Allowance for off-balance sheet credit exposure:
Balance, beginning of period			1,959
Impact of adoption ASU 2016-13 \| Accounting Standards Update 2016-13
Allowance for off-balance sheet credit exposure:
Balance, beginning of period		268
Balance, end of period			268
Residential Real Estate
Allowance for off-balance sheet credit exposure:
Balance, beginning of period	58	37	19
Provision (benefit) charged to expense	13	21	(17)
Balance, end of period	71	58	37
Residential Real Estate \| Impact of adoption ASU 2016-13 \| Accounting Standards Update 2016-13
Allowance for off-balance sheet credit exposure:
Balance, beginning of period		35
Balance, end of period			35
Construction Real Estate
Allowance for off-balance sheet credit exposure:
Balance, beginning of period	2,178	502	769
Provision (benefit) charged to expense	2,631	1,676	(100)
Balance, end of period	4,809	2,178	502
Construction Real Estate \| Impact of adoption ASU 2016-13 \| Accounting Standards Update 2016-13
Allowance for off-balance sheet credit exposure:
Balance, beginning of period		(167)
Balance, end of period			(167)
Commercial Real Estate
Allowance for off-balance sheet credit exposure:
Balance, beginning of period	421	188	172
Provision (benefit) charged to expense	54	233	(79)
Balance, end of period	475	421	188
Commercial Real Estate \| Impact of adoption ASU 2016-13 \| Accounting Standards Update 2016-13
Allowance for off-balance sheet credit exposure:
Balance, beginning of period		95
Balance, end of period			95
Consumer loans
Allowance for off-balance sheet credit exposure:
Balance, beginning of period	61	218	153
Provision (benefit) charged to expense	12	(157)	(132)
Balance, end of period	73	61	218
Consumer loans \| Impact of adoption ASU 2016-13 \| Accounting Standards Update 2016-13
Allowance for off-balance sheet credit exposure:
Balance, beginning of period		197
Balance, end of period			197
Commercial loans
Allowance for off-balance sheet credit exposure:
Balance, beginning of period	640	860	846
Provision (benefit) charged to expense	220	(220)	(94)
Balance, end of period	$ 860	640	860
Commercial loans \| Impact of adoption ASU 2016-13 \| Accounting Standards Update 2016-13
Allowance for off-balance sheet credit exposure:
Balance, beginning of period		$ 108
Balance, end of period			$ 108

Amount of expected credit loss for credit exposure on off-balance-sheet commitment, including but not limited to, loan commitment, standby letter of credit, financial guarantee not accounted for as insurance. Excludes off-balance sheet credit exposure accounted for as insurance and instrument accounted for under derivatives and hedging.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479344/326-20-45-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 460
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482454/460-10-45-1

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Amount of expense (reversal of expense) for expected credit loss for off-balance sheet credit exposure. Excludes off-balance sheet credit exposure accounted for as insurance and instrument accounted for under derivatives and hedging.

+ 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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