Loans (Average Balance and Interest Income of Loans Individually Evaluated for Impairment) (Details) $ in Thousands	12 Months Ended
Dec. 31, 2019 USD ($)
Financing Receivable Impaired No Related Allowance Recorded [Abstract]
Average Recorded Investment	$ 5,912
Interest Income Recognized	101
Cash Basis Recognized	2
Financing Receivable Impaired Allowance Recorded [Abstract]
Average Recorded Investment	6,894
Interest Income Recognized	0
Cash Basis Recognized	2
Average Recorded Investment	12,806
Interest Income Recognized	101
Cash Basis Recognized	4
Loans Acquired With Deteriorated Credit Quality
Financing Receivable Impaired No Related Allowance Recorded [Abstract]
Average Recorded Investment	4,321
Interest Income Recognized	61
Cash Basis Recognized	3
Financing Receivable Impaired Allowance Recorded [Abstract]
Average Recorded Investment	1,766
Interest Income Recognized	0
Cash Basis Recognized	0
Commercial and Industrial Loans and Leases
Financing Receivable Impaired No Related Allowance Recorded [Abstract]
Average Recorded Investment	1,175
Interest Income Recognized	19
Cash Basis Recognized	1
Financing Receivable Impaired Allowance Recorded [Abstract]
Average Recorded Investment	3,753
Interest Income Recognized	0
Cash Basis Recognized	1
Commercial Real Estate Loans
Financing Receivable Impaired No Related Allowance Recorded [Abstract]
Average Recorded Investment	2,947
Interest Income Recognized	81
Cash Basis Recognized	1
Financing Receivable Impaired Allowance Recorded [Abstract]
Average Recorded Investment	3,141
Interest Income Recognized	0
Cash Basis Recognized	1
Agricultural Loans
Financing Receivable Impaired No Related Allowance Recorded [Abstract]
Average Recorded Investment	1,790
Interest Income Recognized	1
Cash Basis Recognized	0
Financing Receivable Impaired Allowance Recorded [Abstract]
Average Recorded Investment	0
Interest Income Recognized	0
Cash Basis Recognized	$ 0

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Financing Receivable, Impaired, No Related Allowance Recorded [Abstract].

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Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
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