Loans (Average Recorded Investment And Interest Income Recognized On Loans Individually Evaluated For Impairment) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Financing Receivable, Impaired [Line Items]
Recorded investment	$ 46,760	$ 73,609	$ 46,760	$ 73,609	$ 56,564
Average recorded investment	54,679	72,580	52,015	68,953
Interest income recognized	485	654	1,292	1,902
Commercial Financial And Agricultural [Member]
Financing Receivable, Impaired [Line Items]
Recorded investment	16,026	29,848	16,026	29,848
Average recorded investment	23,247	28,412	22,686	23,770
Interest income recognized	187	398	506	738
Construction Real Estate Commercial [Domain]
Financing Receivable, Impaired [Line Items]
Recorded investment	2,016	1,460	2,016	1,460
Average recorded investment	2,246	1,554	1,661	1,830
Interest income recognized	4	18	31	49
Residential Real Estate Commercial [Member]
Financing Receivable, Impaired [Line Items]
Recorded investment	2,913	19,298	2,913	19,298
Average recorded investment	2,758	20,365	6,086	20,876
Interest income recognized	26	46	84	452
Commercial Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Recorded investment	25,805	22,995	25,805	22,995
Average recorded investment	26,428	22,241	21,582	22,470
Interest income recognized	$ 268	192	$ 671	663
Consumer [Member]
Financing Receivable, Impaired [Line Items]
Recorded investment		8		8
Average recorded investment		$ 8		$ 7

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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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