Loans And Allowance For Loan Losses (Additional Information About Impaired Loans Held) (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Loans And Allowance For Loan Losses [Line Items]
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	$ 6,103	$ 7,932
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance	9,752	11,222
Impaired Financing Receivable, with Related Allowance, Recorded Investment	59,055	56,600
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	64,081	62,481
Impaired Financing Receivable, Related Allowance	2,887	3,109
Impaired Financing Receivable, Recorded Investment	65,158	64,532
Impaired Financing Receivable, Unpaid Principal Balance	73,833	73,703
Business [Member]
Loans And Allowance For Loan Losses [Line Items]
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	5,566	7,375
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance	9,000	10,470
Impaired Financing Receivable, with No Related Allowance, Allowance	0	0
Impaired Financing Receivable, with Related Allowance, Recorded Investment	29,226	29,924
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	29,821	31,795
Impaired Financing Receivable, Related Allowance	914	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	537	557
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance	752	752
Impaired Financing Receivable, with No Related Allowance, Allowance	0	0
Impaired Financing Receivable, with Related Allowance, Recorded Investment	65	69
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	68	72
Impaired Financing Receivable, Related Allowance	3	3
Real Estate - Business [Member]
Loans And Allowance For Loan Losses [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment	9,543	6,870
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	10,961	8,072
Impaired Financing Receivable, Related Allowance	537	496
Real Estate - Personal [Member]
Loans And Allowance For Loan Losses [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment	6,286	6,394
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	9,258	9,199
Impaired Financing Receivable, Related Allowance	570	642
Consumer [Member]
Loans And Allowance For Loan Losses [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment	6,242	5,281
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	6,280	5,281
Impaired Financing Receivable, Related Allowance	259	57
Revolving Home Equity [Member]
Loans And Allowance For Loan Losses [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment	582	584
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	582	584
Impaired Financing Receivable, Related Allowance	10	1
Consumer Credit Card [Member]
Loans And Allowance For Loan Losses [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment	7,111	7,478
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	7,111	7,478
Impaired Financing Receivable, Related Allowance	$ 594	$ 592

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

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- Definition

Loans And Allowance For Loan Losses [Line Items]

+ References

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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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- Definition

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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- Definition

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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