Loans And Allowance For Loan Losses (Additional Information About Impaired Loans Held) (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Loans And Allowance For Loan Losses [Line Items]
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	$ 7,806	$ 7,932
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance	11,359	11,222
Impaired Financing Receivable, with Related Allowance, Recorded Investment	71,734	56,600
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	76,534	62,481
Impaired Financing Receivable, Related Allowance	3,111	3,109
Impaired Financing Receivable, Recorded Investment	79,540	64,532
Impaired Financing Receivable, Unpaid Principal Balance	87,893	73,703
Business [Member]
Loans And Allowance For Loan Losses [Line Items]
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	6,196	7,375
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance	9,725	10,470
Impaired Financing Receivable, with No Related Allowance, Allowance	0	0
Impaired Financing Receivable, with Related Allowance, Recorded Investment	35,708	29,924
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	36,219	31,795
Impaired Financing Receivable, Related Allowance	1,141	1,318
Real Estate - Construction And Land [Member]
Loans And Allowance For Loan Losses [Line Items]
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	0	557
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance	0	752
Impaired Financing Receivable, with No Related Allowance, Allowance	0	0
Impaired Financing Receivable, with Related Allowance, Recorded Investment	1,367	69
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	1,595	72
Impaired Financing Receivable, Related Allowance	37	3
Real Estate - Business [Member]
Loans And Allowance For Loan Losses [Line Items]
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	587	0
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance	587	0
Impaired Financing Receivable, with No Related Allowance, Allowance	0	0
Impaired Financing Receivable, with Related Allowance, Recorded Investment	12,111	6,870
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	13,319	8,072
Impaired Financing Receivable, Related Allowance	611	496
Real Estate - Personal [Member]
Loans And Allowance For Loan Losses [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment	9,723	6,394
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	12,537	9,199
Impaired Financing Receivable, Related Allowance	607	642
Consumer [Member]
Loans And Allowance For Loan Losses [Line Items]
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	1,023	0
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance	1,047	0
Impaired Financing Receivable, with No Related Allowance, Allowance	0	0
Impaired Financing Receivable, with Related Allowance, Recorded Investment	5,232	5,281
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	5,271	5,281
Impaired Financing Receivable, Related Allowance	52	57
Revolving Home Equity [Member]
Loans And Allowance For Loan Losses [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment	578	584
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	578	584
Impaired Financing Receivable, Related Allowance	5	1
Consumer Credit Card [Member]
Loans And Allowance For Loan Losses [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment	7,015	7,478
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	7,015	7,478
Impaired Financing Receivable, Related Allowance	$ 658	$ 592

Impaired Financing Receivable, with No Related Allowance, Allowance (zero)

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- Definition

Loans And Allowance For Loan Losses [Line Items]

+ References

No definition available.

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- Definition

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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- Definition

Amount of allowance for credit losses related to recorded investment.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Recorded Investment
-URI http://asc.fasb.org/extlink&oid=65880944

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5212-111524

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Amount of unpaid principal balance of impaired financing receivables with related allowance for credit losses and without 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 (a)(4)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5212-111524

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- Definition

Amount of investment in impaired financing receivables for which there is no related allowance for credit losses.

+ References

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Amount of unpaid principal balance of impaired financing receivables for which there is no related allowance for credit losses.

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Amount of investment in impaired financing receivables for which there is a related allowance for credit losses.

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Unpaid principal balance of impaired financing receivables for which there is a related allowance for credit losses.

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