Loans and Allowance for Credit Losses - Allowance for off-balance credit exposure (Details) - USD ($) $ in Thousands	12 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2024
Allowance for off-balance sheet credit exposure:
Balance, beginning of period	$ 3,939	$ 3,263	$ 6,288
Provision (benefit) charged to expense	483	676	(3,025)
Balance, end of period	4,422	3,939	3,263
Commercial and industrial
Allowance for off-balance sheet credit exposure:
Balance, beginning of period	1,074	782	730
Provision (benefit) charged to expense	(430)	292	52
Balance, end of period	644	1,074	782
Agriculture production
Allowance for off-balance sheet credit exposure:
Balance, beginning of period		37	107
Provision (benefit) charged to expense	510	(37)	(70)
Balance, end of period	510		37
Consumer
Allowance for off-balance sheet credit exposure:
Balance, beginning of period		12	16
Provision (benefit) charged to expense	4	(12)	(4)
Balance, end of period	4		12
All other loans
Allowance for off-balance sheet credit exposure:
Balance, beginning of period	8		10
Provision (benefit) charged to expense	(3)	8	(10)
Balance, end of period	5	8
Secured by real estate \| 1-4 Family residential real estate
Allowance for off-balance sheet credit exposure:
Balance, beginning of period	202	140	126
Provision (benefit) charged to expense	30	62	14
Balance, end of period	232	202	140
Secured by real estate \| Commercial Real Estate \| Non-owner occupied
Allowance for off-balance sheet credit exposure:
Balance, beginning of period	134	153	154
Provision (benefit) charged to expense	57	(19)	(1)
Balance, end of period	191	134	153
Secured by real estate \| Commercial Real Estate \| Owner occupied
Allowance for off-balance sheet credit exposure:
Balance, beginning of period	161	136	182
Provision (benefit) charged to expense	51	25	(46)
Balance, end of period	212	161	136
Secured by real estate \| Multi-family real estate
Allowance for off-balance sheet credit exposure:
Balance, beginning of period		31	16
Provision (benefit) charged to expense	44	(31)	15
Balance, end of period	44		31
Secured by real estate \| Construction and land development
Allowance for off-balance sheet credit exposure:
Balance, beginning of period	2,279	1,912	4,897
Provision (benefit) charged to expense	233	367	(2,985)
Balance, end of period	2,512	2,279	1,912
Secured by real estate \| Agriculture real estate
Allowance for off-balance sheet credit exposure:
Balance, beginning of period	81	60	50
Provision (benefit) charged to expense	(13)	21	10
Balance, end of period	$ 68	$ 81	$ 60

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

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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