Loans And Allowance For Loan Losses (Additional Information About Impaired Loans Held) (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Loans And Allowance For Loan Losses [Line Items]
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	$ 8,381	$ 8,725
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance	14,376	14,477
Impaired Financing Receivable, with No Related Allowance, Allowance	0	0
Impaired Financing Receivable, with Related Allowance, Recorded Investment	75,791	69,891
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	78,056	72,597
Impaired Financing Receivable, Related Allowance	2,643	2,696
Impaired Financing Receivable, Recorded Investment	84,172	78,616
Impaired Financing Receivable, Unpaid Principal Balance	92,432	87,074
Business [Member]
Loans And Allowance For Loan Losses [Line Items]
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	8,381	8,725
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance	14,376	14,477
Impaired Financing Receivable, with No Related Allowance, Allowance	0	0
Impaired Financing Receivable, with Related Allowance, Recorded Investment	46,736	40,286
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	46,873	40,582
Impaired Financing Receivable, Related Allowance	1,241	1,223
Real Estate - Construction And Land [Member]
Loans And Allowance For Loan Losses [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment	414	416
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	419	421
Impaired Financing Receivable, Related Allowance	11	11
Real Estate - Business [Member]
Loans And Allowance For Loan Losses [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment	11,208	12,069
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	11,809	12,699
Impaired Financing Receivable, Related Allowance	468	546
Real Estate - Personal [Member]
Loans And Allowance For Loan Losses [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment	4,380	4,461
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	5,902	6,236
Impaired Financing Receivable, Related Allowance	243	266
Consumer [Member]
Loans And Allowance For Loan Losses [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment	5,365	5,510
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	5,365	5,510
Impaired Financing Receivable, Related Allowance	34	38
Revolving Home Equity [Member]
Loans And Allowance For Loan Losses [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment	39	40
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	39	40
Impaired Financing Receivable, Related Allowance	1	1
Consumer Credit Card [Member]
Loans And Allowance For Loan Losses [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment	7,649	7,109
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	7,649	7,109
Impaired Financing Receivable, Related Allowance	$ 645	$ 611

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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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- Definition

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

+ References

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