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Loans and Leases, Components of Loans and Leases (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Jun. 30, 2023	Dec. 31, 2022	Sep. 30, 2022	Jun. 30, 2022	Dec. 31, 2021
Loan & Lease Portfolio [Abstract]
Gross loans and leases	$ 3,567,807		$ 3,521,718
Unearned income	(10,604)		(9,357)
Total net loans and leases	3,557,203		3,512,361
Allowance for credit losses	(74,159)	$ (71,112)	(66,885)	$ (63,617)	$ (62,080)	$ (61,007)
Loans held-for-investment, net	3,483,044		3,445,476
Maximum borrowing capacity	2,200,000		1,500,000
Federal Home Loan Bank [Member]
Loan & Lease Portfolio [Abstract]
Maximum borrowing capacity	794,900
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	1,200,000
Federal Reserve Bank [Member] \| Asset Pledged as Collateral [Member]
Loan & Lease Portfolio [Abstract]
Loans held-for-investment, net	1,500,000
Real Estate [Member]
Loan & Lease Portfolio [Abstract]
Gross loans and leases	2,642,468		2,609,920
Total net loans and leases	2,634,277		2,601,543
Allowance for credit losses	(45,035)		(43,085)
Commercial [Member]
Loan & Lease Portfolio [Abstract]
Gross loans and leases	1,297,380		1,328,691
Total net loans and leases	1,289,189		1,320,314
Allowance for credit losses	(26,724)		(18,055)
Agricultural [Member]
Loan & Lease Portfolio [Abstract]
Gross loans and leases	753,353		726,938
Total net loans and leases	753,353		726,938
Allowance for credit losses	(7,241)		(14,496)
Residential and Home Equity [Member]
Loan & Lease Portfolio [Abstract]
Gross loans and leases	398,990		387,753
Total net loans and leases	398,990		387,753
Allowance for credit losses	(7,458)	(7,179)	(7,508)	(6,865)	(6,874)	(2,847)
Construction [Member]
Loan & Lease Portfolio [Abstract]
Gross loans and leases	192,745		166,538
Total net loans and leases	192,745		166,538
Allowance for credit losses	(3,612)	(3,195)	(3,026)	(2,995)	(2,876)	(1,456)
Commercial & Industrial [Member]
Loan & Lease Portfolio [Abstract]
Gross loans and leases	489,772		478,758
Total net loans and leases	489,772		478,758
Allowance for credit losses	(17,903)		(11,503)
Agricultural [Member]
Loan & Lease Portfolio [Abstract]
Gross loans and leases	301,951		314,525
Total net loans and leases	301,951		314,525
Allowance for credit losses	(9,082)		(10,202)
Commercial Leases [Member]
Loan & Lease Portfolio [Abstract]
Gross loans and leases	128,063		112,629
Total net loans and leases	125,650		111,649
Allowance for credit losses	(1,967)	(1,657)	(1,924)	(1,588)	(1,645)	(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	$ (172)	$ (192)	$ (171)	$ (154)	$ (161)	$ (663)