Loans and Allowance for Credit Losses - Classes of loans (Details)	12 Months Ended
Jun. 30, 2026 USD ($) loan	Jun. 30, 2025 USD ($) loan	Jun. 30, 2024 USD ($)	Jun. 30, 2023 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans (before deferred loan fees, net)	$ 4,391,808,000	$ 4,100,768,000
Deferred loan fees, net	(937,000)	(178,000)
Allowance for credit losses	(54,912,000)	(51,629,000)	$ (52,516,000)	$ (47,820,000)
Net loans	$ 4,336,896,000	$ 4,048,961,000
Number of purchased participation loans \| loan	62	71
Purchased participation loans	$ 147,100,000	$ 188,000,000
Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans (before deferred loan fees, net)	552,557,000	510,259,000
Allowance for credit losses	(6,604,000)	(6,952,000)	(6,233,000)	(5,235,000)
Agriculture production
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans (before deferred loan fees, net)	219,155,000	206,128,000
Allowance for credit losses	(6,275,000)	(3,374,000)	(835,000)	(782,000)
Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans (before deferred loan fees, net)	53,144,000	55,387,000
Allowance for credit losses	(1,043,000)	(952,000)	(578,000)	(490,000)
All other loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans (before deferred loan fees, net)	9,529,000	5,102,000
Allowance for credit losses	(3,000)	(4,000)	(17,000)	(21,000)
Secured by real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans (before deferred loan fees, net)	3,557,423,000	3,323,892,000
Secured by real estate \| 1-4 Family residential real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans (before deferred loan fees, net)	1,085,512,000	992,445,000
Allowance for credit losses	(12,085,000)	(10,274,000)	(10,528,000)	(9,474,000)
Secured by real estate \| Commercial Real Estate \| Non-owner occupied
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans (before deferred loan fees, net)	924,144,000	888,317,000
Allowance for credit losses	(10,952,000)	(12,241,000)	(19,055,000)	(13,863,000)
Secured by real estate \| Commercial Real Estate \| Owner occupied
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans (before deferred loan fees, net)	471,990,000	442,984,000
Allowance for credit losses	(5,265,000)	(4,521,000)	(4,815,000)	(5,168,000)
Secured by real estate \| Multi-family real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans (before deferred loan fees, net)	469,968,000	422,758,000
Allowance for credit losses	(3,095,000)	(4,329,000)	(5,447,000)	(6,806,000)
Secured by real estate \| Construction and land development
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans (before deferred loan fees, net)	310,006,000	332,405,000
Allowance for credit losses	(3,202,000)	(4,788,000)	(2,901,000)	(3,414,000)
Secured by real estate \| Agriculture real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans (before deferred loan fees, net)	295,803,000	244,983,000
Allowance for credit losses	$ (6,388,000)	$ (4,194,000)	$ (2,107,000)	$ (2,567,000)

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