Loans And Allowance For Loan Losses (Additional Information About Impaired Loans Held) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Loans And Allowance For Loan Losses [Line Items]
Impaired Financing Receivable, Recorded Investment	$ 81,732	$ 78,616
Impaired Financing Receivable, Unpaid Principal Balance	90,390	87,074
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	7,054	8,725
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance	13,738	14,477
Impaired Financing Receivable, with No Related Allowance, Allowance	0	0
Impaired Financing Receivable, with Related Allowance, Recorded Investment	74,678	69,891
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	76,652	72,597
Impaired Financing Receivable, Related Allowance	2,746	2,696
Business [Member]
Loans And Allowance For Loan Losses [Line Items]
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	7,054	8,725
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance	13,738	14,477
Impaired Financing Receivable, with No Related Allowance, Allowance	0	0
Impaired Financing Receivable, with Related Allowance, Recorded Investment	30,437	40,286
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	30,487	40,582
Impaired Financing Receivable, Related Allowance	837	1,223
Real Estate - Construction And Land [Member]
Loans And Allowance For Loan Losses [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment	46	416
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	51	421
Impaired Financing Receivable, Related Allowance	1	11
Real Estate - Business [Member]
Loans And Allowance For Loan Losses [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment	26,963	12,069
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	27,643	12,699
Impaired Financing Receivable, Related Allowance	791	546
Real Estate - Personal [Member]
Loans And Allowance For Loan Losses [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment	4,729	4,461
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	5,968	6,236
Impaired Financing Receivable, Related Allowance	258	266
Consumer [Member]
Loans And Allowance For Loan Losses [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment	4,421	5,510
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	4,421	5,510
Impaired Financing Receivable, Related Allowance	35	38
Revolving Home Equity [Member]
Loans And Allowance For Loan Losses [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment	35	40
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	35	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	8,047	7,109
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	8,047	7,109
Impaired Financing Receivable, Related Allowance	$ 823	$ 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=118936363&loc=SL6953550-111524

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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=118936363&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://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=118936363&loc=d3e5212-111524

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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=118936363&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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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=118936363&loc=d3e5212-111524

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