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Loans and Leases, Components of Loans and Leases (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Mar. 31, 2023	Dec. 31, 2022	Jun. 30, 2022	Mar. 31, 2022	Dec. 31, 2021
Loan & Lease Portfolio [Abstract]
Gross loans and leases	$ 3,502,064		$ 3,521,718
Unearned income	(10,341)		(9,357)
Total net loans and leases	3,491,723		3,512,361
Allowance for credit losses	(71,112)	$ (68,573)	(66,885)	$ (62,080)	$ (61,032)	$ (61,007)
Loans held-for-investment, net	3,420,611		3,445,476
Maximum borrowing capacity	1,600,000		1,500,000
Federal Home Loan Bank [Member]
Loan & Lease Portfolio [Abstract]
Maximum borrowing capacity	784,100
Federal Home Loan Bank [Member] \| Asset Pledged as Collateral [Member]
Loan & Lease Portfolio [Abstract]
Loans held-for-investment, net	1,300,000
Federal Reserve Bank [Member]
Loan & Lease Portfolio [Abstract]
Maximum borrowing capacity	655,000
Federal Reserve Bank [Member] \| Asset Pledged as Collateral [Member]
Loan & Lease Portfolio [Abstract]
Loans held-for-investment, net	894,400
Real Estate [Member]
Loan & Lease Portfolio [Abstract]
Gross loans and leases	2,607,324		2,609,920
Total net loans and leases	2,599,081		2,601,543
Allowance for credit losses	(45,069)		(43,085)
Commercial [Member]
Loan & Lease Portfolio [Abstract]
Gross loans and leases	1,302,460		1,328,691
Total net loans and leases	1,294,217		1,320,314
Allowance for credit losses	(24,787)		(18,055)
Agricultural [Member]
Loan & Lease Portfolio [Abstract]
Gross loans and leases	739,207		726,938
Total net loans and leases	739,207		726,938
Allowance for credit losses	(9,908)		(14,496)
Residential and Home Equity [Member]
Loan & Lease Portfolio [Abstract]
Gross loans and leases	392,754		387,753
Total net loans and leases	392,754		387,753
Allowance for credit losses	(7,179)	(7,334)	(7,508)	(6,874)	(6,759)	(2,847)
Construction [Member]
Loan & Lease Portfolio [Abstract]
Gross loans and leases	172,903		166,538
Total net loans and leases	172,903		166,538
Allowance for credit losses	(3,195)	(2,785)	(3,026)	(2,876)	(3,777)	(1,456)
Commercial & Industrial [Member]
Loan & Lease Portfolio [Abstract]
Gross loans and leases	479,908		478,758
Total net loans and leases	479,908		478,758
Allowance for credit losses	(11,291)		(11,503)
Agricultural [Member]
Loan & Lease Portfolio [Abstract]
Gross loans and leases	282,725		314,525
Total net loans and leases	282,725		314,525
Allowance for credit losses	(12,903)		(10,202)
Commercial Leases [Member]
Loan & Lease Portfolio [Abstract]
Gross loans and leases	126,554		112,629
Total net loans and leases	124,456		111,649
Allowance for credit losses	(1,657)	(1,720)	(1,924)	(1,645)	(1,466)	(938)
Consumer and Other [Member]
Loan & Lease Portfolio [Abstract]
Gross loans and leases	5,553		5,886
Total net loans and leases	5,553		5,886
Allowance for credit losses	$ (192)	$ (152)	$ (171)	$ (161)	$ (421)	$ (663)