Loans (Average Recorded Investment And Interest Income Recognized On Loans Individually Evaluated For Impairment) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Financing Receivable, Impaired [Line Items]
Recorded investment	$ 50,322	$ 70,127	$ 56,564
Average recorded investment	50,863	67,950
Interest income recognized	421	811
Commercial Financial And Agricultural [Member]
Financing Receivable, Impaired [Line Items]
Recorded investment	27,050	22,542
Average recorded investment	20,078	19,471
Interest income recognized	174	220
Construction Real Estate Commercial [Domain]
Financing Receivable, Impaired [Line Items]
Recorded investment	1,393	2,041
Average recorded investment	1,377	2,096
Interest income recognized	14	15
Residential Real Estate - Commercial [Member]
Financing Receivable, Impaired [Line Items]
Recorded investment	2,896	22,803
Average recorded investment	11,215	23,081
Interest income recognized	31	345
Commercial Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Recorded investment	18,983	22,732
Average recorded investment	18,193	23,297
Interest income recognized	$ 202	231
Consumer [Member]
Financing Receivable, Impaired [Line Items]
Recorded investment		9
Average recorded investment		$ 5

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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://www.xbrl.org/2003/role/presentationRef
-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://www.xbrl.org/2003/role/presentationRef
-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.

+ References

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- Definition

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://www.xbrl.org/2003/role/presentationRef
-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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