Loans and Allowance for Credit Losses - Allowance for off-balance credit exposure (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Mar. 31, 2026	Mar. 31, 2025	Mar. 31, 2026	Mar. 31, 2025
Allowance for off-balance sheet credit exposure:
Balance, beginning of period	$ 4,298	$ 3,832	$ 3,939	$ 3,263
Provision (benefit) charged to expense	234	(368)	593	201
Balance, end of period	4,532	3,464	4,532	3,464
Commercial and industrial
Allowance for off-balance sheet credit exposure:
Balance, beginning of period	810	1,032	1,074	782
Provision (benefit) charged to expense	18	194	(246)	444
Balance, end of period	828	1,226	828	1,226
Agriculture production
Allowance for off-balance sheet credit exposure:
Balance, beginning of period	275	127		37
Provision (benefit) charged to expense	424	70	699	160
Balance, end of period	699	197	699	197
Consumer
Allowance for off-balance sheet credit exposure:
Balance, beginning of period	4	6		12
Provision (benefit) charged to expense			4	(6)
Balance, end of period	4	6	4	6
All other loans
Allowance for off-balance sheet credit exposure:
Balance, beginning of period	4		8
Provision (benefit) charged to expense	(1)	1	(5)	1
Balance, end of period	3	1	3	1
Secured by real estate \| 1-4 Family residential real estate
Allowance for off-balance sheet credit exposure:
Balance, beginning of period	189	229	202	140
Provision (benefit) charged to expense	8	(33)	(5)	56
Balance, end of period	197	196	197	196
Secured by real estate \| Commercial Real Estate \| Non-owner occupied
Allowance for off-balance sheet credit exposure:
Balance, beginning of period	153	185	134	153
Provision (benefit) charged to expense	29	(17)	48	15
Balance, end of period	182	168	182	168
Secured by real estate \| Commercial Real Estate \| Owner occupied
Allowance for off-balance sheet credit exposure:
Balance, beginning of period	172	169	161	136
Provision (benefit) charged to expense	(1)	5	10	38
Balance, end of period	171	174	171	174
Secured by real estate \| Multi-family real estate
Allowance for off-balance sheet credit exposure:
Balance, beginning of period	45	65		31
Provision (benefit) charged to expense	(3)	(3)	42	31
Balance, end of period	42	62	42	62
Secured by real estate \| Construction and land development
Allowance for off-balance sheet credit exposure:
Balance, beginning of period	2,612	1,965	2,279	1,912
Provision (benefit) charged to expense	(258)	(561)	75	(508)
Balance, end of period	2,354	1,404	2,354	1,404
Secured by real estate \| Agriculture real estate
Allowance for off-balance sheet credit exposure:
Balance, beginning of period	34	54	81	60
Provision (benefit) charged to expense	18	(24)	(29)	(30)
Balance, end of period	$ 52	$ 30	$ 52	$ 30

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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- Definition

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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