Loans (Average Recorded Investment And Interest Income Recognized On Loans Individually Evaluated For Impairment) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Financing Receivable, Impaired [Line Items]
Recorded investment	$ 61,750	$ 73,144	$ 61,750	$ 73,144	$ 56,564
Average recorded investment	52,511	67,672	51,883	67,479
Interest income recognized	386	437	807	1,248
Commercial Financial And Agricultural [Member]
Financing Receivable, Impaired [Line Items]
Recorded investment	29,943	28,475	29,943	28,475
Average recorded investment	27,637	23,320	23,402	21,789
Interest income recognized	145	120	319	340
Construction Real Estate Commercial [Domain]
Financing Receivable, Impaired [Line Items]
Recorded investment	2,529	1,636	2,529	1,636
Average recorded investment	1,510	1,843	1,451	1,960
Interest income recognized	13	16	27	31
Residential Real Estate - Commercial [Member]
Financing Receivable, Impaired [Line Items]
Recorded investment	2,750	21,235	2,750	21,235
Average recorded investment	2,653	20,732	7,511	21,220
Interest income recognized	27	61	58	406
Commercial Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Recorded investment	26,528	21,790	26,528	21,790
Average recorded investment	20,711	21,768	19,519	22,504
Interest income recognized	$ 201	240	$ 403	471
Consumer [Member]
Financing Receivable, Impaired [Line Items]
Recorded investment		8		8
Average recorded investment		$ 9		$ 6

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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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.

+ References

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)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5212-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5258-111524

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Amount of interest income recognized on a cash-basis method of accounting that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

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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)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953550-111524

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