Loans (Activity in Allowance for Loan Losses Prior to Adoption of ASC 326) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	$ 16,278	$ 15,823	$ 15,694
Provision for Loan Losses	17,550	5,325	2,070
Recoveries	514	532	605
Loans Charged-off	(3,136)	(5,402)	(2,546)
Ending Balance	46,859	16,278	15,823
Commercial and Industrial Loans and Leases
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	4,799	2,953	4,735
Provision for Loan Losses		5,600	(423)
Recoveries		56	141
Loans Charged-off		(3,810)	(1,500)
Ending Balance		4,799	2,953
Commercial Real Estate Loans
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	4,692	5,291	4,591
Provision for Loan Losses	17,645	(308)	729
Recoveries	129	29	20
Loans Charged-off	(36)	(320)	(49)
Ending Balance	29,878	4,692	5,291
Agricultural Loans
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	5,315	5,776	4,894
Provision for Loan Losses	(125)	(461)	862
Recoveries	0	0	20
Loans Charged-off	0	0	0
Ending Balance	6,756	5,315	5,776
Home Equity Loans
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	200	229	330
Provision for Loan Losses	66	(27)	(52)
Recoveries	0	8	12
Loans Charged-off	(67)	(10)	(61)
Ending Balance	996	200	229
Consumer Loans
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	434	420	298
Provision for Loan Losses	527	727	608
Recoveries	354	432	375
Loans Charged-off	(766)	(1,145)	(861)
Ending Balance	490	434	420
Residential Mortgage Loans
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	333	472	343
Provision for Loan Losses	(95)	(29)	167
Recoveries	4	7	37
Loans Charged-off	(39)	(117)	(75)
Ending Balance	1,944	333	472
Unallocated
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	505	682	503
Provision for Loan Losses	0	(177)	179
Recoveries	0	0	0
Loans Charged-off	0	0	0
Ending Balance	$ 0	$ 505	$ 682

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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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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