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Loans and Leases - Components of Loans and Leases (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Mar. 31, 2026	Dec. 31, 2025	Jun. 30, 2025	Mar. 31, 2025	Dec. 31, 2024
Loans and Leases [Abstract]
Gross loans and leases	$ 3,721,425		$ 3,667,325
Unearned income	(17,568)		(18,380)
Total net loans and leases	3,703,857		3,648,945
Allowance for credit losses	(77,253)	$ (76,918)	(76,375)	$ (76,169)	$ (75,423)	$ (75,283)
Loans held for investment, net	3,626,604		3,572,570
Commercial [Member]
Loans and Leases [Abstract]
Gross loans and leases	1,541,826		1,480,906
Total net loans and leases	1,533,656		1,472,583
Allowance for credit losses	(22,979)	(21,935)	(22,574)	(20,946)	(20,313)	(20,382)
Agricultural [Member]
Loans and Leases [Abstract]
Gross loans and leases	692,554		705,668
Total net loans and leases	692,554		705,668
Allowance for credit losses	(23,007)	(22,481)	(23,647)	(24,469)	(24,077)	(23,615)
Residential and Home Equity [Member]
Loans and Leases [Abstract]
Gross loans and leases	404,005		405,080
Total net loans and leases	404,005		405,080
Allowance for credit losses	(7,664)	(7,480)	(7,620)	(7,599)	(7,479)	(7,340)
Construction [Member]
Loans and Leases [Abstract]
Gross loans and leases	115,150		128,179
Total net loans and leases	115,150		128,179
Allowance for credit losses	(2,089)	(2,846)	(2,311)	(2,766)	(2,648)	(3,055)
Real Estate [Member]
Loans and Leases [Abstract]
Gross loans and leases	2,753,535		2,719,833
Total net loans and leases	2,745,365		2,711,510
Allowance for credit losses	(55,739)	(54,742)	(56,152)	(55,780)	(54,517)	(54,392)
Commercial & Industrial [Member]
Loans and Leases [Abstract]
Gross loans and leases	527,508		497,700
Total net loans and leases	527,508		497,700
Allowance for credit losses	(8,646)	(9,100)	(7,355)	(7,326)	(7,843)	(7,791)
Agricultural [Member]
Loans and Leases [Abstract]
Gross loans and leases	255,767		264,117
Total net loans and leases	255,767		264,117
Allowance for credit losses	(7,023)	(7,173)	(6,760)	(6,982)	(6,417)	(6,725)
Commercial Leases [Member]
Loans and Leases [Abstract]
Gross loans and leases	180,223		181,004
Total net loans and leases	170,825		170,947
Allowance for credit losses	(5,618)	(5,682)	(5,861)	(5,858)	(6,429)	(6,153)
Consumer and Other [Member]
Loans and Leases [Abstract]
Gross loans and leases	4,392		4,671
Total net loans and leases	4,392		4,671
Allowance for credit losses	$ (227)	$ (221)	$ (247)	$ (223)	$ (217)	$ (222)