Loans (Loans Individually And Collectively Evaluated For Impairment) (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2017	Dec. 31, 2016
Financing Receivable, Impaired [Line Items]
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	$ 5,102	$ 548
Nonaccrual and accruing restructured loans	110,071	106,050
Nonaccrual and accruing restructured loans, loans individually evaluated for impairment	73,609	70,426
Nonaccrual and accruing restructured loans, loans collectively evaluated for impairment	36,462	35,624
Partial Charge-Offs On Impaired Loans	9,946	24,943
Commercial Financial And Agricultural [Member]
Financing Receivable, Impaired [Line Items]
Nonaccrual and accruing restructured loans	29,878	20,657
Nonaccrual and accruing restructured loans, loans individually evaluated for impairment	29,848	20,624
Nonaccrual and accruing restructured loans, loans collectively evaluated for impairment	30	33
Construction Real Estate Commercial [Domain]
Financing Receivable, Impaired [Line Items]
Nonaccrual and accruing restructured loans	1,460	2,226
Nonaccrual and accruing restructured loans, loans individually evaluated for impairment	1,460	2,226
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	92	104
Nonaccrual and accruing restructured loans, loans individually evaluated for impairment	0	0
Nonaccrual and accruing restructured loans, loans collectively evaluated for impairment	92	104
Construction Real Estate - Installment [Member]
Financing Receivable, Impaired [Line Items]
Nonaccrual and accruing restructured loans	57	156
Nonaccrual and accruing restructured loans, loans individually evaluated for impairment	0	0
Nonaccrual and accruing restructured loans, loans collectively evaluated for impairment	57	156
Residential Real Estate - Commercial [Member]
Financing Receivable, Impaired [Line Items]
Nonaccrual and accruing restructured loans	19,298	23,102
Nonaccrual and accruing restructured loans, loans individually evaluated for impairment	19,298	23,102
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	28,459	27,925
Nonaccrual and accruing restructured loans, loans individually evaluated for impairment	0	0
Nonaccrual and accruing restructured loans, loans collectively evaluated for impairment	28,459	27,925
Residential Real Estate - HELOC [Member]
Financing Receivable, Impaired [Line Items]
Nonaccrual and accruing restructured loans	2,608	2,456
Nonaccrual and accruing restructured loans, loans individually evaluated for impairment	0	0
Nonaccrual and accruing restructured loans, loans collectively evaluated for impairment	2,608	2,456
Residential Real Estate - Installment [Member]
Financing Receivable, Impaired [Line Items]
Nonaccrual and accruing restructured loans	1,334	1,253
Nonaccrual and accruing restructured loans, loans individually evaluated for impairment	0	0
Nonaccrual and accruing restructured loans, loans collectively evaluated for impairment	1,334	1,253
Commercial Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	320	309
Nonaccrual and accruing restructured loans	22,995	24,474
Nonaccrual and accruing restructured loans, loans individually evaluated for impairment	22,995	24,474
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	8	0
Nonaccrual and accruing restructured loans	3,890	3,697
Nonaccrual and accruing restructured loans, loans individually evaluated for impairment	8
Nonaccrual and accruing restructured loans, loans collectively evaluated for impairment	3,882	3,697
Financing Receivable With No Related Allowance Recorded [Member]
Financing Receivable, Impaired [Line Items]
Partial Charge-Offs On Impaired Loans	$ 7,500	$ 24,700

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

No definition available.

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- Definition

Partial Charge-Offs On Impaired Loans

+ References

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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=84173941&loc=SL6953423-111524

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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