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, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Financing Receivable, Impaired [Line Items]
Recorded investment	$ 73,144	$ 90,844	$ 73,144	$ 90,844	$ 70,426
Average recorded investment	67,672	81,825	67,479	80,544
Interest income recognized	437	848	1,248	3,244
Commercial Financial And Agricultural [Member]
Financing Receivable, Impaired [Line Items]
Recorded investment	28,475	29,779	28,475	29,779
Average recorded investment	23,320	28,600	21,789	29,319
Interest income recognized	120	308	340	546
Construction Real Estate Commercial [Domain]
Financing Receivable, Impaired [Line Items]
Recorded investment	1,636	6,086	1,636	6,086
Average recorded investment	1,843	6,395	1,960	6,564
Interest income recognized	16	15	31	28
Residential Real Estate - Commercial [Member]
Financing Receivable, Impaired [Line Items]
Recorded investment	21,235	25,070	21,235	25,070
Average recorded investment	20,732	24,648	21,220	24,795
Interest income recognized	61	340	406	2,305
Commercial Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Recorded investment	21,790	29,889	21,790	29,889
Average recorded investment	21,768	22,177	22,504	19,863
Interest income recognized	240	185	471	365
Consumer [Member]
Financing Receivable, Impaired [Line Items]
Recorded investment	8	20	8	20
Average recorded investment	$ 9	$ 5	$ 6	$ 3

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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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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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