Loans and Allowance for Credit Losses - Allowance for off-balance credit exposure (Details) - USD ($)	3 Months Ended
	Sep. 30, 2024	Sep. 30, 2023
Allowance for off-balance sheet credit exposure:
Balance, beginning of period	$ 3,263,000	$ 6,288,000
Provision (benefit) charged to expense	138,000	(670,000)
Balance, end of period	3,401,000	5,618,000
Commercial and industrial
Allowance for off-balance sheet credit exposure:
Balance, beginning of period	782,000	730,000
Provision (benefit) charged to expense	20,000	37,000
Balance, end of period	802,000	767,000
Agriculture production
Allowance for off-balance sheet credit exposure:
Balance, beginning of period	37,000	107,000
Provision (benefit) charged to expense	(3,000)	(84,000)
Balance, end of period	34,000	23,000
Consumer
Allowance for off-balance sheet credit exposure:
Balance, beginning of period	12,000	16,000
Provision (benefit) charged to expense		1,000
Balance, end of period	12,000	17,000
All other loans
Allowance for off-balance sheet credit exposure:
Balance, beginning of period		10,000
Provision (benefit) charged to expense		(3,000)
Balance, end of period		7,000
Secured by real estate | 1-4 residential real estate
Allowance for off-balance sheet credit exposure:
Balance, beginning of period	140,000	126,000
Provision (benefit) charged to expense	30,000	5,000
Balance, end of period	170,000	131,000
Secured by real estate | Commercial Real Estate | Non-owner occupied
Allowance for off-balance sheet credit exposure:
Balance, beginning of period	153,000	154,000
Provision (benefit) charged to expense	22,000
Balance, end of period	175,000	154,000
Secured by real estate | Commercial Real Estate | Owner occupied
Allowance for off-balance sheet credit exposure:
Balance, beginning of period	136,000	182,000
Provision (benefit) charged to expense	(14,000)	(2,000)
Balance, end of period	122,000	180,000
Secured by real estate | Multi-family real estate
Allowance for off-balance sheet credit exposure:
Balance, beginning of period	31,000	16,000
Provision (benefit) charged to expense	3,000	(1,000)
Balance, end of period	34,000	15,000
Secured by real estate | Construction and land development
Allowance for off-balance sheet credit exposure:
Balance, beginning of period	1,912,000	4,897,000
Provision (benefit) charged to expense	88,000	(612,000)
Balance, end of period	2,000,000	4,285,000
Secured by real estate | Agriculture real estate
Allowance for off-balance sheet credit exposure:
Balance, beginning of period	60,000	50,000
Provision (benefit) charged to expense	(8,000)	(11,000)
Balance, end of period	$ 52,000	$ 39,000