Loans and Allowance for Credit Losses - Allowance for off-balance credit exposure (Details) - USD ($) $ in Thousands	3 Months Ended
Sep. 30, 2025	Sep. 30, 2024
Allowance for off-balance sheet credit exposure:
Balance, beginning of period	$ 3,939	$ 3,263
Provision (benefit) charged to expense	359	138
Balance, end of period	4,298	3,401
Commercial and industrial
Allowance for off-balance sheet credit exposure:
Balance, beginning of period	1,074	782
Provision (benefit) charged to expense	(270)	20
Balance, end of period	804	802
Agriculture production
Allowance for off-balance sheet credit exposure:
Balance, beginning of period		37
Provision (benefit) charged to expense		(3)
Balance, end of period		34
Consumer
Allowance for off-balance sheet credit exposure:
Balance, beginning of period		12
Provision (benefit) charged to expense	3
Balance, end of period	3	12
All other loans
Allowance for off-balance sheet credit exposure:
Balance, beginning of period	8
Balance, end of period	8
Secured by real estate \| 1-4 Family residential real estate
Allowance for off-balance sheet credit exposure:
Balance, beginning of period	202	140
Provision (benefit) charged to expense	(20)	30
Balance, end of period	182	170
Secured by real estate \| Commercial Real Estate \| Non-owner occupied
Allowance for off-balance sheet credit exposure:
Balance, beginning of period	134	153
Provision (benefit) charged to expense	26	22
Balance, end of period	160	175
Secured by real estate \| Commercial Real Estate \| Owner occupied
Allowance for off-balance sheet credit exposure:
Balance, beginning of period	161	136
Provision (benefit) charged to expense	(28)	(14)
Balance, end of period	133	122
Secured by real estate \| Multi-family real estate
Allowance for off-balance sheet credit exposure:
Balance, beginning of period		31
Provision (benefit) charged to expense	63	3
Balance, end of period	63	34
Secured by real estate \| Construction and land development
Allowance for off-balance sheet credit exposure:
Balance, beginning of period	2,279	1,912
Provision (benefit) charged to expense	575	88
Balance, end of period	2,854	2,000
Secured by real estate \| Agriculture real estate
Allowance for off-balance sheet credit exposure:
Balance, beginning of period	81	60
Provision (benefit) charged to expense	10	(8)
Balance, end of period	$ 91	$ 52

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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