Loans (Loans Individually And Collectively Evaluated For Impairment) (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2016	Dec. 31, 2015
Financing Receivable, Impaired [Line Items]
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	$ 4,930	$ 4,191
Nonaccrual and accruing restructured loans	117,719	120,975
Nonaccrual and accruing restructured loans, loans individually evaluated for impairment	78,171	80,664
Nonaccrual and accruing restructured loans, loans collectively evaluated for impairment	39,548	40,311
Partial Charge-Offs On Impaired Loans	28,422	28,705
Commercial Financial And Agricultural [Member]
Financing Receivable, Impaired [Line Items]
Nonaccrual and accruing restructured loans	28,610	30,623
Nonaccrual and accruing restructured loans, loans individually evaluated for impairment	28,596	30,595
Nonaccrual and accruing restructured loans, loans collectively evaluated for impairment	14	28
Construction Real Estate, SEPH Commercial Land and Development [Member]
Financing Receivable, Impaired [Line Items]
Nonaccrual and accruing restructured loans	2,043	2,044
Nonaccrual and accruing restructured loans, loans individually evaluated for impairment	2,043	2,044
Construction Real Estate - Remaining Commercial [Member]
Financing Receivable, Impaired [Line Items]
Nonaccrual and accruing restructured loans	4,845	4,676
Nonaccrual and accruing restructured loans, loans individually evaluated for impairment	4,845	4,676
Nonaccrual and accruing restructured loans, loans collectively evaluated for impairment	0	0
Construction Real Estate - Mortgage [Member]
Financing Receivable, Impaired [Line Items]
Nonaccrual and accruing restructured loans	114	117
Nonaccrual and accruing restructured loans, loans individually evaluated for impairment	0	0
Nonaccrual and accruing restructured loans, loans collectively evaluated for impairment	114	117
Construction Real Estate - Installment [Member]
Financing Receivable, Impaired [Line Items]
Nonaccrual and accruing restructured loans	129	178
Nonaccrual and accruing restructured loans, loans individually evaluated for impairment	0	0
Nonaccrual and accruing restructured loans, loans collectively evaluated for impairment	129	178
Residential Real Estate - Commercial [Member]
Financing Receivable, Impaired [Line Items]
Nonaccrual and accruing restructured loans	24,619	25,324
Nonaccrual and accruing restructured loans, loans individually evaluated for impairment	24,619	25,324
Nonaccrual and accruing restructured loans, loans collectively evaluated for impairment	0	0
Residential Real Estate - Mortgage [Member]
Financing Receivable, Impaired [Line Items]
Nonaccrual and accruing restructured loans	30,580	30,521
Nonaccrual and accruing restructured loans, loans individually evaluated for impairment	0	0
Nonaccrual and accruing restructured loans, loans collectively evaluated for impairment	30,580	30,521
Residential Real Estate - HELOC [Member]
Financing Receivable, Impaired [Line Items]
Nonaccrual and accruing restructured loans	2,482	2,622
Nonaccrual and accruing restructured loans, loans individually evaluated for impairment	0	0
Nonaccrual and accruing restructured loans, loans collectively evaluated for impairment	2,482	2,622
Residential Real Estate - Installment [Member]
Financing Receivable, Impaired [Line Items]
Nonaccrual and accruing restructured loans	2,053	2,292
Nonaccrual and accruing restructured loans, loans individually evaluated for impairment	0	0
Nonaccrual and accruing restructured loans, loans collectively evaluated for impairment	2,053	2,292
Commercial Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	593	381
Nonaccrual and accruing restructured loans	18,068	18,025
Nonaccrual and accruing restructured loans, loans individually evaluated for impairment	18,068	18,025
Nonaccrual and accruing restructured loans, loans collectively evaluated for impairment	0	0
Consumer [Member]
Financing Receivable, Impaired [Line Items]
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	0	0
Nonaccrual and accruing restructured loans	4,176	4,553
Nonaccrual and accruing restructured loans, loans collectively evaluated for impairment	4,176	4,553
Financing Receivable With No Related Allowance Recorded [Member]
Financing Receivable, Impaired [Line Items]
Partial Charge-Offs On Impaired Loans	$ 24,000	$ 24,200

Financing receivable recorded investment nonaccrual and accruing restructured loans.

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- Definition

Financing Receivable Recorded Investment Nonaccrual And Accruing Restructured Loans, Collectively Evaluated for Impairment

+ References

No definition available.

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- Definition

Financing Receivable Recorded Investment Nonaccrual And Accruing Restructured Loans, Individually Evaluated for Impairment

+ References

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- Definition

Partial Charge-Offs On Impaired Loans

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- Definition

Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953423-111524

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