Loans and Allowance for Credit Losses - Classes of loans (Details) $ in Thousands	6 Months Ended	12 Months Ended
	Dec. 31, 2024 USD ($) loan	Jun. 30, 2024 USD ($) loan	Sep. 30, 2024 USD ($)	Dec. 31, 2023 USD ($)	Sep. 30, 2023 USD ($)	Jun. 30, 2023 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans (before deferred loan fees, net)	$ 4,027,181	$ 3,850,035
Deferred loan fees, net	(202)	(232)
Allowance for credit losses	(54,740)	(52,516)	$ (54,437)	$ (50,084)	$ (49,122)	$ (47,820)
Net loans	$ 3,972,239	$ 3,797,287
Number of purchased participation loans | loan	75	71
Purchased participation loans	$ 220,500	$ 178,500
Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans (before deferred loan fees, net)	484,799	450,147
Allowance for credit losses	(8,063)	(6,233)	(6,114)	(5,850)	(5,134)	(5,235)
Agriculture production
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans (before deferred loan fees, net)	188,284	175,968
Allowance for credit losses	(1,060)	(835)	(784)	(570)	(697)	(782)
Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans (before deferred loan fees, net)	56,017	59,671
Allowance for credit losses	(603)	(578)	(526)	(454)	(453)	(490)
All other loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans (before deferred loan fees, net)	3,628	3,981
Allowance for credit losses	(24)	(17)	(14)	(17)	(16)	(21)
Secured by real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans (before deferred loan fees, net)	3,294,453	3,160,268
Allowance for credit losses	(12,664)		(10,637)	(9,574)	(9,371)
Secured by real estate | 1-4 residential real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans (before deferred loan fees, net)	967,196	925,397
Allowance for credit losses	(12,664)	(10,528)		(9,574)		(9,474)
Secured by real estate | 1-4 residential real estate | Non-owner occupied
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses	(13,660)		(20,728)
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)	882,484	899,770
Allowance for credit losses	(13,660)	(19,055)		(16,599)	(16,504)	(13,863)
Secured by real estate | Commercial Real Estate | Owner occupied
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans (before deferred loan fees, net)	435,392	427,476
Allowance for credit losses	(5,707)	(4,815)	(4,814)	(4,814)	(4,879)	(5,168)
Secured by real estate | Multi-family real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans (before deferred loan fees, net)	376,081	384,564
Allowance for credit losses	(5,725)	(5,447)	(5,118)	(6,188)	(6,097)	(6,806)
Secured by real estate | Construction and land development
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans (before deferred loan fees, net)	393,388	290,541
Allowance for credit losses	(4,717)	(2,901)	(3,675)	(3,639)	(3,545)	(3,414)
Secured by real estate | Agriculture real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans (before deferred loan fees, net)	239,912	232,520
Allowance for credit losses	$ (2,517)	$ (2,107)	$ (2,027)	$ (2,379)	$ (2,426)	$ (2,567)