Loans (Activity in Allowance for Credit Losses) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Allowance for Credit Losses [Roll Forward]
Beginning Balance	$ 16,278	$ 15,823	$ 15,694
Provision for credit loss expense	17,550	5,325	2,070
Initial allowance on loans purchased with credit deterioration	0
Loans Charged-off	(3,136)	(5,402)	(2,546)
Recoveries collected	514	532	605
Ending Balance	46,859	16,278	15,823
Impact of adopting ASC 326 - PCD Loans
Allowance for Credit Losses [Roll Forward]
Beginning Balance	405
Ending Balance		405
Impact of ASC 326 Adoption \| Impact of adopting ASC 326
Allowance for Credit Losses [Roll Forward]
Beginning Balance	8,767
Ending Balance		8,767
Impact of ASC 326 Adoption \| Impact of adopting ASC 326 - PCD Loans
Allowance for Credit Losses [Roll Forward]
Beginning Balance	6,886
Ending Balance		6,886
Commercial and Industrial Loans
Allowance for Credit Losses [Roll Forward]
Beginning Balance	4,799
Provision for credit loss expense	(694)
Initial allowance on loans purchased with credit deterioration	0
Loans Charged-off	(2,119)
Recoveries collected	23
Ending Balance	6,445	4,799
Commercial and Industrial Loans \| Impact of ASC 326 Adoption \| Impact of adopting ASC 326
Allowance for Credit Losses [Roll Forward]
Beginning Balance	2,245
Ending Balance		2,245
Commercial and Industrial Loans \| Impact of ASC 326 Adoption \| Impact of adopting ASC 326 - PCD Loans
Allowance for Credit Losses [Roll Forward]
Beginning Balance	2,191
Ending Balance		2,191
Commercial Real Estate Loans
Allowance for Credit Losses [Roll Forward]
Beginning Balance	4,692	5,291	4,591
Provision for credit loss expense	17,645	(308)	729
Initial allowance on loans purchased with credit deterioration	0
Loans Charged-off	(36)	(320)	(49)
Recoveries collected	129	29	20
Ending Balance	29,878	4,692	5,291
Commercial Real Estate Loans \| Impact of adopting ASC 326 - PCD Loans
Allowance for Credit Losses [Roll Forward]
Beginning Balance	400
Ending Balance		400
Commercial Real Estate Loans \| Impact of ASC 326 Adoption \| Impact of adopting ASC 326
Allowance for Credit Losses [Roll Forward]
Beginning Balance	3,063
Ending Balance		3,063
Commercial Real Estate Loans \| Impact of ASC 326 Adoption \| Impact of adopting ASC 326 - PCD Loans
Allowance for Credit Losses [Roll Forward]
Beginning Balance	4,385
Ending Balance		4,385
Agricultural Loans
Allowance for Credit Losses [Roll Forward]
Beginning Balance	5,315	5,776	4,894
Provision for credit loss expense	(125)	(461)	862
Initial allowance on loans purchased with credit deterioration	0
Loans Charged-off	0	0	0
Recoveries collected	0	0	20
Ending Balance	6,756	5,315	5,776
Agricultural Loans \| Impact of adopting ASC 326 - PCD Loans
Allowance for Credit Losses [Roll Forward]
Beginning Balance	0
Ending Balance		0
Agricultural Loans \| Impact of ASC 326 Adoption \| Impact of adopting ASC 326
Allowance for Credit Losses [Roll Forward]
Beginning Balance	1,438
Ending Balance		1,438
Agricultural Loans \| Impact of ASC 326 Adoption \| Impact of adopting ASC 326 - PCD Loans
Allowance for Credit Losses [Roll Forward]
Beginning Balance	128
Ending Balance		128
Leases
Allowance for Credit Losses [Roll Forward]
Beginning Balance	0
Provision for credit loss expense	95
Initial allowance on loans purchased with credit deterioration	0
Loans Charged-off	0
Recoveries collected	0
Ending Balance	200	0
Leases \| Impact of ASC 326 Adoption \| Impact of adopting ASC 326
Allowance for Credit Losses [Roll Forward]
Beginning Balance	105
Ending Balance		105
Leases \| Impact of ASC 326 Adoption \| Impact of adopting ASC 326 - PCD Loans
Allowance for Credit Losses [Roll Forward]
Beginning Balance	0
Ending Balance		0
Consumer Loans
Allowance for Credit Losses [Roll Forward]
Beginning Balance	434	420	298
Provision for credit loss expense	527	727	608
Initial allowance on loans purchased with credit deterioration	0
Loans Charged-off	(766)	(1,145)	(861)
Recoveries collected	354	432	375
Ending Balance	490	434	420
Consumer Loans \| Impact of adopting ASC 326 - PCD Loans
Allowance for Credit Losses [Roll Forward]
Beginning Balance	0
Ending Balance		0
Consumer Loans \| Impact of ASC 326 Adoption \| Impact of adopting ASC 326
Allowance for Credit Losses [Roll Forward]
Beginning Balance	(59)
Ending Balance		(59)
Consumer Loans \| Impact of ASC 326 Adoption \| Impact of adopting ASC 326 - PCD Loans
Allowance for Credit Losses [Roll Forward]
Beginning Balance	0
Ending Balance		0
Home Equity Loans
Allowance for Credit Losses [Roll Forward]
Beginning Balance	200	229	330
Provision for credit loss expense	66	(27)	(52)
Initial allowance on loans purchased with credit deterioration	0
Loans Charged-off	(67)	(10)	(61)
Recoveries collected	0	8	12
Ending Balance	996	200	229
Home Equity Loans \| Impact of adopting ASC 326 - PCD Loans
Allowance for Credit Losses [Roll Forward]
Beginning Balance	0
Ending Balance		0
Home Equity Loans \| Impact of ASC 326 Adoption \| Impact of adopting ASC 326
Allowance for Credit Losses [Roll Forward]
Beginning Balance	762
Ending Balance		762
Home Equity Loans \| Impact of ASC 326 Adoption \| Impact of adopting ASC 326 - PCD Loans
Allowance for Credit Losses [Roll Forward]
Beginning Balance	35
Ending Balance		35
Credit Cards
Allowance for Credit Losses [Roll Forward]
Beginning Balance	0
Provision for credit loss expense	131
Initial allowance on loans purchased with credit deterioration	0
Loans Charged-off	(109)
Recoveries collected	4
Ending Balance	150	0
Credit Cards \| Impact of ASC 326 Adoption \| Impact of adopting ASC 326
Allowance for Credit Losses [Roll Forward]
Beginning Balance	124
Ending Balance		124
Credit Cards \| Impact of ASC 326 Adoption \| Impact of adopting ASC 326 - PCD Loans
Allowance for Credit Losses [Roll Forward]
Beginning Balance	0
Ending Balance		0
Residential Mortgage Loans
Allowance for Credit Losses [Roll Forward]
Beginning Balance	333	472	343
Provision for credit loss expense	(95)	(29)	167
Initial allowance on loans purchased with credit deterioration	0
Loans Charged-off	(39)	(117)	(75)
Recoveries collected	4	7	37
Ending Balance	1,944	333	472
Residential Mortgage Loans \| Impact of adopting ASC 326 - PCD Loans
Allowance for Credit Losses [Roll Forward]
Beginning Balance	5
Ending Balance		5
Residential Mortgage Loans \| Impact of ASC 326 Adoption \| Impact of adopting ASC 326
Allowance for Credit Losses [Roll Forward]
Beginning Balance	1,594
Ending Balance		1,594
Residential Mortgage Loans \| Impact of ASC 326 Adoption \| Impact of adopting ASC 326 - PCD Loans
Allowance for Credit Losses [Roll Forward]
Beginning Balance	147
Ending Balance		147
Unallocated
Allowance for Credit Losses [Roll Forward]
Beginning Balance	505	682	503
Provision for credit loss expense	0	(177)	179
Initial allowance on loans purchased with credit deterioration	0
Loans Charged-off	0	0	0
Recoveries collected	0	0	0
Ending Balance	0	505	$ 682
Unallocated \| Impact of adopting ASC 326 - PCD Loans
Allowance for Credit Losses [Roll Forward]
Beginning Balance	0
Ending Balance		0
Unallocated \| Impact of ASC 326 Adoption \| Impact of adopting ASC 326
Allowance for Credit Losses [Roll Forward]
Beginning Balance	(505)
Ending Balance		(505)
Unallocated \| Impact of ASC 326 Adoption \| Impact of adopting ASC 326 - PCD Loans
Allowance for Credit Losses [Roll Forward]
Beginning Balance	$ 0
Ending Balance		$ 0

Amount of increase in allowance for credit loss on financing receivable purchased with credit deterioration.

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Amount of increase in allowance for credit loss on financing receivable from recovery.

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Amount of writeoff of financing receivable, charged against allowance for credit loss.

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Amount of credit loss expense (reversal of expense) for financing receivable.

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