Loans (Loans Individually And Collectively Evaluated For Impairment) (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2018	Dec. 31, 2017
Financing Receivable, Impaired [Line Items]
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	$ 1,846	$ 684
Nonaccrual and accruing restructured loans	81,361	92,233
Nonaccrual and accruing restructured loans, loans individually evaluated for impairment	46,760	56,564
Nonaccrual and accruing restructured loans, loans collectively evaluated for impairment	34,601	35,669
Partial Charge-Offs On Impaired Loans	11,069	10,040
Commercial Financial And Agricultural [Member]
Financing Receivable, Impaired [Line Items]
Nonaccrual and accruing restructured loans	16,101	18,064
Nonaccrual and accruing restructured loans, loans individually evaluated for impairment	16,026	18,039
Nonaccrual and accruing restructured loans, loans collectively evaluated for impairment	75	25
Construction Real Estate Commercial [Domain]
Financing Receivable, Impaired [Line Items]
Nonaccrual and accruing restructured loans	2,016	1,324
Nonaccrual and accruing restructured loans, loans individually evaluated for impairment	2,016	1,324
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	32	100
Nonaccrual and accruing restructured loans, loans individually evaluated for impairment	0	0
Nonaccrual and accruing restructured loans, loans collectively evaluated for impairment	32	100
Construction Real Estate - Installment [Member]
Financing Receivable, Impaired [Line Items]
Nonaccrual and accruing restructured loans	33	52
Nonaccrual and accruing restructured loans, loans individually evaluated for impairment	0	0
Nonaccrual and accruing restructured loans, loans collectively evaluated for impairment	33	52
Residential Real Estate Commercial [Member]
Financing Receivable, Impaired [Line Items]
Nonaccrual and accruing restructured loans	2,913	19,059
Nonaccrual and accruing restructured loans, loans individually evaluated for impairment	2,913	19,059
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	25,586	27,607
Nonaccrual and accruing restructured loans, loans individually evaluated for impairment	0	0
Nonaccrual and accruing restructured loans, loans collectively evaluated for impairment	25,586	27,607
Residential Real Estate - HELOC [Member]
Financing Receivable, Impaired [Line Items]
Nonaccrual and accruing restructured loans	3,152	2,618
Nonaccrual and accruing restructured loans, loans individually evaluated for impairment	0	0
Nonaccrual and accruing restructured loans, loans collectively evaluated for impairment	3,152	2,618
Residential Real Estate - Installment [Member]
Financing Receivable, Impaired [Line Items]
Nonaccrual and accruing restructured loans	1,484	1,202
Nonaccrual and accruing restructured loans, loans individually evaluated for impairment	0	0
Nonaccrual and accruing restructured loans, loans collectively evaluated for impairment	1,484	1,202
Commercial Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	71	2
Nonaccrual and accruing restructured loans	25,805	18,142
Nonaccrual and accruing restructured loans, loans individually evaluated for impairment	25,805	18,142
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	4,239	4,065
Nonaccrual and accruing restructured loans, loans collectively evaluated for impairment	4,239	4,065
Financing Receivable With No Related Allowance Recorded [Member]
Financing Receivable, Impaired [Line Items]
Partial Charge-Offs On Impaired Loans	$ 8,900	$ 7,900

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

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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://fasb.org/us-gaap/role/ref/legacyRef
-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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