Loans And Allowance For Credit Losses (Additional Information About Impaired Loans Held) (Details) $ in Thousands	Dec. 31, 2019 USD ($)
Loans And Allowance For Loan Losses [Line Items]
Impaired Financing Receivable, Recorded Investment	$ 81,732
Impaired Financing Receivable, Unpaid Principal Balance	90,390
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	7,054
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance	13,738
Impaired Financing Receivable, with No Related Allowance, Allowance	0
Impaired Financing Receivable, with Related Allowance, Recorded Investment	74,678
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	76,652
Impaired Financing Receivable, Related Allowance	2,746
Business [Member]
Loans And Allowance For Loan Losses [Line Items]
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	7,054
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance	13,738
Impaired Financing Receivable, with No Related Allowance, Allowance	0
Impaired Financing Receivable, with Related Allowance, Recorded Investment	30,437
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	30,487
Impaired Financing Receivable, Related Allowance	837
Real Estate - Construction And Land [Member]
Loans And Allowance For Loan Losses [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment	46
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	51
Impaired Financing Receivable, Related Allowance	1
Real Estate - Business [Member]
Loans And Allowance For Loan Losses [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment	26,963
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	27,643
Impaired Financing Receivable, Related Allowance	791
Real Estate - Personal [Member]
Loans And Allowance For Loan Losses [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment	4,729
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	5,968
Impaired Financing Receivable, Related Allowance	258
Consumer [Member]
Loans And Allowance For Loan Losses [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment	4,421
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	4,421
Impaired Financing Receivable, Related Allowance	35
Revolving Home Equity [Member]
Loans And Allowance For Loan Losses [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment	35
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	35
Impaired Financing Receivable, Related Allowance	1
Consumer Credit Card [Member]
Loans And Allowance For Loan Losses [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment	8,047
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance	8,047
Impaired Financing Receivable, Related Allowance	$ 823

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

No definition available.

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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://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=121611835&loc=SL6953550-111524

+ Details

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Namespace Prefix:	us-gaap_
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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=121611835&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=121611835&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=121611835&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=121611835&loc=d3e5212-111524

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