Loans and Allowance for Credit Losses - Classes of loans (Details) $ in Thousands	3 Months Ended	12 Months Ended
Sep. 30, 2025 USD ($) loan	Jun. 30, 2025 USD ($) loan	Sep. 30, 2024 USD ($)	Jun. 30, 2024 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans (before deferred loan fees, net)	$ 4,191,743	$ 4,100,768
Deferred loan fees, net		(178)
Allowance for credit losses	(52,081)	(51,629)	$ (54,437)	$ (52,516)
Net loans	$ 4,139,662	$ 4,048,961
Number of purchased participation loans \| loan	70	71
Purchased participation loans	$ 155,300	$ 188,000
Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans (before deferred loan fees, net)	521,945	510,259
Allowance for credit losses	(7,833)	(6,952)	(6,114)	(6,233)
Agriculture production
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans (before deferred loan fees, net)	229,338	206,128
Allowance for credit losses	(3,608)	(3,374)	(784)	(835)
Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans (before deferred loan fees, net)	56,051	55,387
Allowance for credit losses	(1,144)	(952)	(526)	(578)
All other loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans (before deferred loan fees, net)	5,094	5,102
Allowance for credit losses	(2)	(4)	(14)	(17)
Secured by real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans (before deferred loan fees, net)	3,379,315	3,323,892
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)	1,021,300	992,445
Allowance for credit losses	(11,434)	(10,274)	(10,637)	(10,528)
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)	918,275	888,317
Allowance for credit losses	(10,514)	(12,241)	(20,728)	(19,055)
Secured by real estate \| Commercial Real Estate \| Owner occupied
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans (before deferred loan fees, net)	454,265	442,984
Allowance for credit losses	(4,332)	(4,521)	(4,814)	(4,815)
Secured by real estate \| Multi-family real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans (before deferred loan fees, net)	445,953	422,758
Allowance for credit losses	(3,979)	(4,329)	(5,118)	(5,447)
Secured by real estate \| Construction and land development
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans (before deferred loan fees, net)	283,912	332,405
Allowance for credit losses	(4,473)	(4,788)	(3,675)	(2,901)
Secured by real estate \| Agriculture real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans (before deferred loan fees, net)	255,610	244,983
Allowance for credit losses	$ (4,762)	$ (4,194)	$ (2,027)	$ (2,107)

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