Loans (Components of Loans) (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020	Mar. 31, 2020	Jan. 01, 2020	Dec. 31, 2019
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 3,120,981	$ 3,091,998			$ 3,081,973
Less: Unearned Income	(3,778)	(3,926)
Allowance for Credit Losses	(45,099)	(46,859)	$ (36,641)	$ (31,931)	(16,278)
Loans, Net	3,072,104	3,041,213
Commercial and Industrial Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	672,300	638,773		534,692	589,758
Allowance for Credit Losses	(6,248)	(6,445)	(8,814)		(4,799)
Commercial Real Estate Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	1,492,617	1,467,397		1,500,247	1,495,862
Allowance for Credit Losses	(28,540)	(29,878)	(17,310)		(4,692)
Agricultural Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	347,231	376,186		384,654	384,526
Allowance for Credit Losses	(6,462)	(6,756)	(6,485)		(5,315)
Leases
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	55,714	55,664		57,257
Allowance for Credit Losses	(201)	(200)	(172)		0
Home Equity Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	212,306	219,348		225,790	225,755
Allowance for Credit Losses	(965)	(996)	(977)		(200)
Consumer Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	60,570	66,717		69,264	81,217
Allowance for Credit Losses	(439)	(490)	(455)		(434)
Credit Cards
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	12,609	11,637		11,953
Allowance for Credit Losses	(162)	(150)	(124)		0
Residential Mortgage Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	267,634	256,276		$ 305,002	304,855
Allowance for Credit Losses	(2,082)	(1,944)	$ (2,304)		$ (333)
Commercial | Commercial and Industrial Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	672,300	638,773
Commercial | Commercial Real Estate Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	1,492,617	1,467,397
Commercial | Agricultural Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	347,231	376,186
Commercial | Leases
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	55,714	55,664
Retail | Home Equity Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	212,306	219,348
Retail | Consumer Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	60,570	66,717
Retail | Credit Cards
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	12,609	11,637
Retail | Residential Mortgage Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 267,634	$ 256,276