Loans And Allowance For Loan Losses (Additional Information About Impaired Loans Held) (Details) - USD ($)	Jun. 30, 2018	Dec. 31, 2017
Loans And Allowance For Loan Losses [Line Items]
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	$ 6,156,000	$ 7,434,000
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance	10,236,000	11,120,000
Impaired Financing Receivable, with No Related Allowance, Allowance	0	0
Impaired Financing Receivable, with Related Allowance, Recorded Investment	102,740,000	107,361,000
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	106,030,000	111,309,000
Impaired Financing Receivable, Related Allowance	3,550,000	4,243,000
Impaired Financing Receivable, Recorded Investment	108,896,000	114,795,000
Impaired Financing Receivable, Unpaid Principal Balance	116,266,000	122,429,000
Business [Member]
Loans And Allowance For Loan Losses [Line Items]
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	4,946,000	5,356,000
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance	8,936,000	9,000,000
Impaired Financing Receivable, with No Related Allowance, Allowance	0	0
Impaired Financing Receivable, with Related Allowance, Recorded Investment	70,871,000	72,589,000
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	71,157,000	73,168,000
Impaired Financing Receivable, Related Allowance	2,090,000	2,455,000
Real Estate - Construction And Land [Member]
Loans And Allowance For Loan Losses [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment	1,342,000	837,000
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	1,346,000	841,000
Impaired Financing Receivable, Related Allowance	39,000	27,000
Real Estate - Business [Member]
Loans And Allowance For Loan Losses [Line Items]
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	1,210,000	1,299,000
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance	1,300,000	1,303,000
Impaired Financing Receivable, with No Related Allowance, Allowance	0	0
Impaired Financing Receivable, with Related Allowance, Recorded Investment	12,355,000	12,532,000
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	12,928,000	13,071,000
Impaired Financing Receivable, Related Allowance	502,000	585,000
Real Estate - Personal [Member]
Loans And Allowance For Loan Losses [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment	5,707,000	9,126,000
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	8,134,000	11,914,000
Impaired Financing Receivable, Related Allowance	295,000	532,000
Consumer [Member]
Loans And Allowance For Loan Losses [Line Items]
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	0	779,000
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance	0	817,000
Impaired Financing Receivable, with No Related Allowance, Allowance	0	0
Impaired Financing Receivable, with Related Allowance, Recorded Investment	5,464,000	5,388,000
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	5,464,000	5,426,000
Impaired Financing Receivable, Related Allowance	52,000	67,000
Revolving Home Equity [Member]
Loans And Allowance For Loan Losses [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment	114,000	204,000
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	114,000	204,000
Impaired Financing Receivable, Related Allowance	11,000	11,000
Consumer Credit Card [Member]
Loans And Allowance For Loan Losses [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment	6,887,000	6,685,000
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	6,887,000	6,685,000
Impaired Financing Receivable, Related Allowance	$ 561,000	$ 566,000

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=84173941&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
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=84173941&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=84173941&loc=d3e5212-111524

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

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- Definition

Amount of unpaid principal balance of impaired financing receivables for which there is no 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=84173941&loc=d3e5212-111524

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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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- Definition

Unpaid principal balance of impaired financing receivables for which there is 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 15
-Subparagraph (a)(4)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5212-111524

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