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Loans and Leases, Components of Loans and Leases (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Mar. 31, 2024	Dec. 31, 2023	Jun. 30, 2023	Mar. 31, 2023	Dec. 31, 2022
Loan & Lease Portfolio [Abstract]
Gross loans and leases	$ 3,692,237		$ 3,665,397
Unearned income	(9,867)		(10,708)
Total net loans and leases	3,682,370		3,654,689
Allowance for credit losses	(75,032)	$ (75,018)	(74,965)	$ (71,112)	$ (68,573)	$ (66,885)
Loans and leases held for investment, net	3,607,338		3,579,724
Remaining borrowing capacity	2,100,000		2,200,000
Federal Home Loan Bank [Member]
Loan & Lease Portfolio [Abstract]
Collateral amount	1,300,000
Remaining borrowing capacity	810,200
Federal Reserve Bank [Member]
Loan & Lease Portfolio [Abstract]
Collateral amount	1,500,000
Remaining borrowing capacity	1,200,000
Real Estate [Member]
Loan & Lease Portfolio [Abstract]
Gross loans and leases	2,696,561		2,677,391
Total net loans and leases	2,689,077		2,669,281
Allowance for credit losses	(48,843)		(46,039)
Commercial [Member]
Loan & Lease Portfolio [Abstract]
Gross loans and leases	1,363,198		1,323,038
Total net loans and leases	1,355,714		1,314,928
Allowance for credit losses	(22,608)		(26,093)
Agricultural [Member]
Loan & Lease Portfolio [Abstract]
Gross loans and leases	726,128		742,009
Total net loans and leases	726,128		742,009
Allowance for credit losses	(16,486)		(7,744)
Residential and Home Equity [Member]
Loan & Lease Portfolio [Abstract]
Gross loans and leases	406,562		399,982
Total net loans and leases	406,562		399,982
Allowance for credit losses	(7,584)	(7,721)	(7,770)	(7,179)	(7,334)	(7,508)
Construction [Member]
Loan & Lease Portfolio [Abstract]
Gross loans and leases	200,673		212,362
Total net loans and leases	200,673		212,362
Allowance for credit losses	(2,165)	(4,616)	(4,432)	(3,195)	(2,785)	(3,026)
Commercial & Industrial [Member]
Loan & Lease Portfolio [Abstract]
Gross loans and leases	498,844		499,373
Total net loans and leases	498,844		499,373
Allowance for credit losses	(10,972)		(13,380)
Agricultural [Member]
Loan & Lease Portfolio [Abstract]
Gross loans and leases	312,882		313,737
Total net loans and leases	312,882		313,737
Allowance for credit losses	(6,908)		(8,872)
Commercial Leases [Member]
Loan & Lease Portfolio [Abstract]
Gross loans and leases	178,252		169,684
Total net loans and leases	175,869		167,086
Allowance for credit losses	(7,597)	(6,923)	(6,537)	(1,657)	(1,720)	(1,924)
Consumer and Other [Member]
Loan & Lease Portfolio [Abstract]
Gross loans and leases	5,698		5,212
Total net loans and leases	5,698		5,212
Allowance for credit losses	$ (712)	$ (116)	$ (137)	$ (192)	$ (152)	$ (171)