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Loans and Allowance for Credit Losses - Nonaccrual Loans (Details)	3 Months Ended	12 Months Ended
	Sep. 30, 2025 USD ($) loan	Jun. 30, 2025 USD ($) loan
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual loans	$ 26,031,000	$ 23,040,000
Number of non accrual loans | loan	36	4
Nonaccrual loans individually evaluated for which no ACL was recorded	$ 17,900,000	$ 7,400,000
Allowance for credit loss individually evaluated non accrual loans	0	0
Commercial and industrial
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual loans	5,500,000	3,442,000
Agriculture production
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual loans	269,000	505,000
Consumer
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual loans	38,000	96,000
Secured by real estate | 1-4 Family residential real estate
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual loans	$ 4,607,000	2,847,000
Number of non accrual loans secured | loan	3
Secured by real estate | Commercial Real Estate | Non-owner occupied
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual loans	$ 6,396,000	5,784,000
Secured by real estate | Commercial Real Estate | Owner occupied
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual loans	394,000	1,309,000
Secured by real estate | Construction and land development
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual loans	5,928,000	5,789,000
Secured by real estate | Agriculture real estate
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual loans	$ 2,899,000	$ 3,268,000
Real estate and equipment | Commercial Real Estate
Financing Receivable, Nonaccrual [Line Items]
Number of non accrual loans secured | loan	2

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