Loans (Loans Individually Evaluated For Impairment By Class Of Loans) (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019	Mar. 31, 2019
Financing Receivable, Impaired [Line Items]
Unpaid principal balance	$ 86,379	$ 78,178
Recorded investment	85,851	77,491	$ 50,907
Allowance for loan losses allocated	5,531	5,230
Commercial Financial And Agricultural [Member]
Financing Receivable, Impaired [Line Items]
Recorded investment	29,542		14,844
Commercial Financial And Agricultural [Member] \| Financing Receivable With No Related Allowance Recorded [Member]
Financing Receivable, Impaired [Line Items]
Unpaid principal balance	17,334	21,194
Recorded investment	17,137	21,010
Allowance for loan losses allocated	0	0
Commercial Financial And Agricultural [Member] \| Financing Receivable With A Related Allowance Recorded [Member]
Financing Receivable, Impaired [Line Items]
Unpaid principal balance	12,586	12,289
Recorded investment	12,405	12,078
Allowance for loan losses allocated	5,365	5,104
Construction Real Estate Commercial [Domain]
Financing Receivable, Impaired [Line Items]
Recorded investment	452		2,879
Construction Real Estate Commercial [Domain] \| Financing Receivable With No Related Allowance Recorded [Member]
Financing Receivable, Impaired [Line Items]
Unpaid principal balance	452	453
Recorded investment	452	453
Allowance for loan losses allocated	0	0
Residential Real Estate Commercial [Member]
Financing Receivable, Impaired [Line Items]
Recorded investment	5,581		2,046
Residential Real Estate Commercial [Member] \| Financing Receivable With No Related Allowance Recorded [Member]
Financing Receivable, Impaired [Line Items]
Unpaid principal balance	5,545	1,921
Recorded investment	5,478	1,854
Allowance for loan losses allocated	0	0
Residential Real Estate Commercial [Member] \| Financing Receivable With A Related Allowance Recorded [Member]
Financing Receivable, Impaired [Line Items]
Unpaid principal balance	103	171
Recorded investment	103	171
Allowance for loan losses allocated	25	42
Commercial Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Recorded investment	50,147		$ 31,138
Commercial Real Estate [Member] \| Financing Receivable With No Related Allowance Recorded [Member]
Financing Receivable, Impaired [Line Items]
Unpaid principal balance	49,676	41,696
Recorded investment	49,593	41,471
Allowance for loan losses allocated	0	0
Commercial Real Estate [Member] \| Financing Receivable With A Related Allowance Recorded [Member]
Financing Receivable, Impaired [Line Items]
Unpaid principal balance	554	320
Recorded investment	554	320
Allowance for loan losses allocated	96	35
Finance Leases Portfolio Segment [Member]
Financing Receivable, Impaired [Line Items]
Recorded investment	129
Finance Leases Portfolio Segment [Member] \| Financing Receivable With No Related Allowance Recorded [Member]
Financing Receivable, Impaired [Line Items]
Allowance for loan losses allocated	0	0
Finance Leases Portfolio Segment [Member] \| Financing Receivable With A Related Allowance Recorded [Member]
Financing Receivable, Impaired [Line Items]
Unpaid principal balance	129	134
Recorded investment	129	134
Allowance for loan losses allocated	$ 45	$ 49

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
-Subparagraph (b)
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Amount of allowance for credit losses related to recorded investment.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=121611835&loc=d3e5212-111524

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
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