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Loans and Leases, Components of Loans and Leases (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Jun. 30, 2024	Dec. 31, 2023	Sep. 30, 2023	Jun. 30, 2023	Dec. 31, 2022
Loan & Lease Portfolio [Abstract]
Gross loans and leases	$ 3,713,735		$ 3,665,397
Unearned income	(9,626)		(10,708)
Total net loans and leases	3,704,109		3,654,689
Allowance for credit losses	(75,816)	$ (75,032)	(74,965)	$ (74,159)	$ (71,112)	$ (66,885)
Loans and leases held for investment, net	3,628,293		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	789,600
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	2,699,230		2,677,391
Total net loans and leases	2,691,904		2,669,281
Allowance for credit losses	(54,896)		(46,039)
Commercial [Member]
Loan & Lease Portfolio [Abstract]
Gross loans and leases	1,352,983		1,323,038
Total net loans and leases	1,345,657		1,314,928
Allowance for credit losses	(21,038)		(26,093)
Agricultural [Member]
Loan & Lease Portfolio [Abstract]
Gross loans and leases	737,274		742,009
Total net loans and leases	737,274		742,009
Allowance for credit losses	(23,418)		(7,744)
Residential and Home Equity [Member]
Loan & Lease Portfolio [Abstract]
Gross loans and leases	403,096		399,982
Total net loans and leases	403,096		399,982
Allowance for credit losses	(6,967)	(7,584)	(7,770)	(7,458)	(7,179)	(7,508)
Construction [Member]
Loan & Lease Portfolio [Abstract]
Gross loans and leases	205,877		212,362
Total net loans and leases	205,877		212,362
Allowance for credit losses	(3,473)	(2,165)	(4,432)	(3,612)	(3,195)	(3,026)
Commercial & Industrial [Member]
Loan & Lease Portfolio [Abstract]
Gross loans and leases	530,564		499,373
Total net loans and leases	530,564		499,373
Allowance for credit losses	(7,791)		(13,380)
Agricultural [Member]
Loan & Lease Portfolio [Abstract]
Gross loans and leases	304,425		313,737
Total net loans and leases	304,425		313,737
Allowance for credit losses	(6,929)		(8,872)
Commercial Leases [Member]
Loan & Lease Portfolio [Abstract]
Gross loans and leases	174,293		169,684
Total net loans and leases	171,993		167,086
Allowance for credit losses	(5,969)	(7,597)	(6,537)	(1,967)	(1,657)	(1,924)
Consumer and Other [Member]
Loan & Lease Portfolio [Abstract]
Gross loans and leases	5,223		5,212
Total net loans and leases	5,223		5,212
Allowance for credit losses	$ (231)	$ (712)	$ (137)	$ (172)	$ (192)	$ (171)