Loans (Average Recorded Investment And Interest Income Recognized On Loans Individually Evaluated For Impairment) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Financing Receivable, Impaired [Line Items]
Recorded investment	$ 78,171	$ 70,492	$ 80,664
Average recorded investment	78,669	72,000
Interest income recognized	2,396	562
Commercial Financial And Agricultural [Member]
Financing Receivable, Impaired [Line Items]
Recorded investment	28,596	20,571
Average recorded investment	29,858	19,876
Interest income recognized	238	131
Construction Real Estate, SEPH Commercial Land and Development [Member]
Financing Receivable, Impaired [Line Items]
Recorded investment	2,043	2,077
Average recorded investment	2,043	2,077
Interest income recognized	0	8
Construction Real Estate - Remaining Commercial [Member]
Financing Receivable, Impaired [Line Items]
Recorded investment	4,845	5,725
Average recorded investment	4,771	5,697
Interest income recognized	13	5
Residential Real Estate - Commercial [Member]
Financing Receivable, Impaired [Line Items]
Recorded investment	24,619	25,219
Average recorded investment	24,897	25,373
Interest income recognized	1,965	255
Commercial Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Recorded investment	18,068	16,900
Average recorded investment	17,100	18,977
Interest income recognized	$ 180	$ 163

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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=66008989&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=66008989&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=66008989&loc=SL6953550-111524

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