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Loans and Leases, Components of Loans and Leases (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022	Mar. 31, 2022	Dec. 31, 2021
Loan & Lease Portfolio [Abstract]
Gross loans and leases	$ 3,437,591	$ 3,521,718
Unearned income	(10,458)	(9,357)
Total net loans and leases	3,427,133	3,512,361
Allowance for credit losses	(68,573)	(66,885)	$ (61,032)	$ (61,007)
Loans held-for-investment, net	3,358,560	3,445,476
Maximum borrowing capacity	1,550,000	1,510,000
Federal Home Loan Bank [Member]
Loan & Lease Portfolio [Abstract]
Maximum borrowing capacity	770,700
Federal Home Loan Bank [Member] \| Asset Pledged as Collateral [Member]
Loan & Lease Portfolio [Abstract]
Loans held-for-investment, net	1,200,000
Federal Reserve Bank [Member]
Loan & Lease Portfolio [Abstract]
Maximum borrowing capacity	656,500
Federal Reserve Bank [Member] \| Asset Pledged as Collateral [Member]
Loan & Lease Portfolio [Abstract]
Loans held-for-investment, net	881,500
Real Estate [Member]
Loan & Lease Portfolio [Abstract]
Gross loans and leases	2,560,921	2,609,920
Total net loans and leases	2,552,615	2,601,543
Allowance for credit losses	(42,813)	(43,085)
Commercial [Member]
Loan & Lease Portfolio [Abstract]
Gross loans and leases	1,312,745	1,328,691
Total net loans and leases	1,304,439	1,320,314
Allowance for credit losses	(24,253)	(18,055)
Agricultural [Member]
Loan & Lease Portfolio [Abstract]
Gross loans and leases	707,412	726,938
Total net loans and leases	707,412	726,938
Allowance for credit losses	(8,441)	(14,496)
Residential and Home Equity [Member]
Loan & Lease Portfolio [Abstract]
Gross loans and leases	387,370	387,753
Total net loans and leases	387,370	387,753
Allowance for credit losses	(7,334)	(7,508)	(6,759)	(2,847)
Construction [Member]
Loan & Lease Portfolio [Abstract]
Gross loans and leases	153,394	166,538
Total net loans and leases	153,394	166,538
Allowance for credit losses	(2,785)	(3,026)	(3,777)	(1,456)
Commercial and Industrial [Member]
Loan & Lease Portfolio [Abstract]
Gross loans and leases	472,189	478,758
Total net loans and leases	472,189	478,758
Allowance for credit losses	(11,346)	(11,503)
Agricultural [Member]
Loan & Lease Portfolio [Abstract]
Gross loans and leases	275,785	314,525
Total net loans and leases	275,785	314,525
Allowance for credit losses	(12,542)	(10,202)
Commercial Leases [Member]
Loan & Lease Portfolio [Abstract]
Gross loans and leases	123,314	112,629
Total net loans and leases	121,162	111,649
Allowance for credit losses	(1,720)	(1,924)	(1,466)	(938)
Consumer and Other [Member]
Loan & Lease Portfolio [Abstract]
Gross loans and leases	5,382	5,886
Total net loans and leases	5,382	5,886
Allowance for credit losses	$ (152)	$ (171)	$ (421)	$ (663)