Loans and Leases, Credit Risk Rating Categories for Loans and Leases Held-for-Investment (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 Allocated by Management's Internal Risk Ratings [Abstract]
Gross 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
Pass [Member]
Loan & Lease Portfolio Allocated by Management's Internal Risk Ratings [Abstract]
Gross loans and leases	3,638,968		3,618,482
Special Mention [Member]
Loan & Lease Portfolio Allocated by Management's Internal Risk Ratings [Abstract]
Gross loans and leases	41,427		34,240
Substandard [Member]
Loan & Lease Portfolio Allocated by Management's Internal Risk Ratings [Abstract]
Gross loans and leases	1,975		1,967
Doubtful [Member]
Loan & Lease Portfolio Allocated by Management's Internal Risk Ratings [Abstract]
Gross loans and leases	0		0
Real Estate [Member]
Loan & Lease Portfolio Allocated by Management's Internal Risk Ratings [Abstract]
Gross loans and leases	2,689,077		2,669,281
Allowance for credit losses	48,843		46,039
Real Estate [Member] | Pass [Member]
Loan & Lease Portfolio Allocated by Management's Internal Risk Ratings [Abstract]
Gross loans and leases	2,656,853		2,649,431
Real Estate [Member] | Special Mention [Member]
Loan & Lease Portfolio Allocated by Management's Internal Risk Ratings [Abstract]
Gross loans and leases	30,968		18,540
Real Estate [Member] | Substandard [Member]
Loan & Lease Portfolio Allocated by Management's Internal Risk Ratings [Abstract]
Gross loans and leases	1,256		1,310
Real Estate [Member] | Doubtful [Member]
Loan & Lease Portfolio Allocated by Management's Internal Risk Ratings [Abstract]
Gross loans and leases	0		0
Commercial [Member]
Loan & Lease Portfolio Allocated by Management's Internal Risk Ratings [Abstract]
Gross loans and leases	1,355,714		1,314,928
Allowance for credit losses	22,608		26,093
Commercial [Member] | Pass [Member]
Loan & Lease Portfolio Allocated by Management's Internal Risk Ratings [Abstract]
Gross loans and leases	1,352,338		1,308,717
Commercial [Member] | Special Mention [Member]
Loan & Lease Portfolio Allocated by Management's Internal Risk Ratings [Abstract]
Gross loans and leases	3,376		6,211
Commercial [Member] | Substandard [Member]
Loan & Lease Portfolio Allocated by Management's Internal Risk Ratings [Abstract]
Gross loans and leases	0		0
Commercial [Member] | Doubtful [Member]
Loan & Lease Portfolio Allocated by Management's Internal Risk Ratings [Abstract]
Gross loans and leases	0		0
Agricultural [Member]
Loan & Lease Portfolio Allocated by Management's Internal Risk Ratings [Abstract]
Gross loans and leases	726,128		742,009
Allowance for credit losses	16,486		7,744
Agricultural [Member] | Pass [Member]
Loan & Lease Portfolio Allocated by Management's Internal Risk Ratings [Abstract]
Gross loans and leases	698,104		729,135
Agricultural [Member] | Special Mention [Member]
Loan & Lease Portfolio Allocated by Management's Internal Risk Ratings [Abstract]
Gross loans and leases	27,478		12,329
Agricultural [Member] | Substandard [Member]
Loan & Lease Portfolio Allocated by Management's Internal Risk Ratings [Abstract]
Gross loans and leases	546		545
Agricultural [Member] | Doubtful [Member]
Loan & Lease Portfolio Allocated by Management's Internal Risk Ratings [Abstract]
Gross loans and leases	0		0
Residential and Home Equity [Member]
Loan & Lease Portfolio Allocated by Management's Internal Risk Ratings [Abstract]
Gross loans and leases	406,562		399,982
Allowance for credit losses	7,584	7,721	7,770	7,179	7,334	7,508
Residential and Home Equity [Member] | Pass [Member]
Loan & Lease Portfolio Allocated by Management's Internal Risk Ratings [Abstract]
Gross loans and leases	405,738		399,217
Residential and Home Equity [Member] | Special Mention [Member]
Loan & Lease Portfolio Allocated by Management's Internal Risk Ratings [Abstract]
Gross loans and leases	114		0
Residential and Home Equity [Member] | Substandard [Member]
Loan & Lease Portfolio Allocated by Management's Internal Risk Ratings [Abstract]
Gross loans and leases	710		765
Residential and Home Equity [Member] | Doubtful [Member]
Loan & Lease Portfolio Allocated by Management's Internal Risk Ratings [Abstract]
Gross loans and leases	0		0
Construction [Member]
Loan & Lease Portfolio Allocated by Management's Internal Risk Ratings [Abstract]
Gross loans and leases	200,673		212,362
Allowance for credit losses	2,165	4,616	4,432	3,195	2,785	3,026
Construction [Member] | Pass [Member]
Loan & Lease Portfolio Allocated by Management's Internal Risk Ratings [Abstract]
Gross loans and leases	200,673		212,362
Construction [Member] | Special Mention [Member]
Loan & Lease Portfolio Allocated by Management's Internal Risk Ratings [Abstract]
Gross loans and leases	0		0
Construction [Member] | Substandard [Member]
Loan & Lease Portfolio Allocated by Management's Internal Risk Ratings [Abstract]
Gross loans and leases	0		0
Construction [Member] | Doubtful [Member]
Loan & Lease Portfolio Allocated by Management's Internal Risk Ratings [Abstract]
Gross loans and leases	0		0
Commercial & Industrial [Member]
Loan & Lease Portfolio Allocated by Management's Internal Risk Ratings [Abstract]
Gross loans and leases	498,844		499,373
Allowance for credit losses	10,972		13,380
Commercial & Industrial [Member] | Pass [Member]
Loan & Lease Portfolio Allocated by Management's Internal Risk Ratings [Abstract]
Gross loans and leases	493,400		486,439
Commercial & Industrial [Member] | Special Mention [Member]
Loan & Lease Portfolio Allocated by Management's Internal Risk Ratings [Abstract]
Gross loans and leases	4,979		12,458
Commercial & Industrial [Member] | Substandard [Member]
Loan & Lease Portfolio Allocated by Management's Internal Risk Ratings [Abstract]
Gross loans and leases	465		476
Commercial & Industrial [Member] | Doubtful [Member]
Loan & Lease Portfolio Allocated by Management's Internal Risk Ratings [Abstract]
Gross loans and leases	0		0
Agricultural [Member]
Loan & Lease Portfolio Allocated by Management's Internal Risk Ratings [Abstract]
Gross loans and leases	312,882		313,737
Allowance for credit losses	6,908		8,872
Agricultural [Member] | Pass [Member]
Loan & Lease Portfolio Allocated by Management's Internal Risk Ratings [Abstract]
Gross loans and leases	312,126		310,496
Agricultural [Member] | Special Mention [Member]
Loan & Lease Portfolio Allocated by Management's Internal Risk Ratings [Abstract]
Gross loans and leases	710		3,236
Agricultural [Member] | Substandard [Member]
Loan & Lease Portfolio Allocated by Management's Internal Risk Ratings [Abstract]
Gross loans and leases	46		5
Agricultural [Member] | Doubtful [Member]
Loan & Lease Portfolio Allocated by Management's Internal Risk Ratings [Abstract]
Gross loans and leases	0		0
Commercial Leases [Member]
Loan & Lease Portfolio Allocated by Management's Internal Risk Ratings [Abstract]
Gross loans and leases	175,869		167,086
Allowance for credit losses	7,597	6,923	6,537	1,657	1,720	1,924
Commercial Leases [Member] | Pass [Member]
Loan & Lease Portfolio Allocated by Management's Internal Risk Ratings [Abstract]
Gross loans and leases	171,099		167,080
Commercial Leases [Member] | Special Mention [Member]
Loan & Lease Portfolio Allocated by Management's Internal Risk Ratings [Abstract]
Gross loans and leases	4,770		6
Commercial Leases [Member] | Substandard [Member]
Loan & Lease Portfolio Allocated by Management's Internal Risk Ratings [Abstract]
Gross loans and leases	0		0
Commercial Leases [Member] | Doubtful [Member]
Loan & Lease Portfolio Allocated by Management's Internal Risk Ratings [Abstract]
Gross loans and leases	0		0
Consumer and Other [Member]
Loan & Lease Portfolio Allocated by Management's Internal Risk Ratings [Abstract]
Gross loans and leases	5,698		5,212
Allowance for credit losses	712	$ 116	137	$ 192	$ 152	$ 171
Consumer and Other [Member] | Pass [Member]
Loan & Lease Portfolio Allocated by Management's Internal Risk Ratings [Abstract]
Gross loans and leases	5,490		5,036
Consumer and Other [Member] | Special Mention [Member]
Loan & Lease Portfolio Allocated by Management's Internal Risk Ratings [Abstract]
Gross loans and leases	0		0
Consumer and Other [Member] | Substandard [Member]
Loan & Lease Portfolio Allocated by Management's Internal Risk Ratings [Abstract]
Gross loans and leases	208		176
Consumer and Other [Member] | Doubtful [Member]
Loan & Lease Portfolio Allocated by Management's Internal Risk Ratings [Abstract]
Gross loans and leases	$ 0		$ 0