Loans And The Allowance For Loan Losses (TDR Activity By Type Of Concession Granted To Borrower) (Details) $ in Thousands	12 Months Ended
Dec. 31, 2017 USD ($) contract	Dec. 31, 2016 USD ($) contract
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract
Pre-Modification Outstanding Recorded Investment
Post-Modification Outstanding Recorded Investment
Commercial And Industrial [Member] \| Deferral Of Principal [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	1
Pre-Modification Outstanding Recorded Investment	$ 874
Post-Modification Outstanding Recorded Investment	$ 874
Commercial And Industrial [Member] \| Extension Of Maturity [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract		2
Pre-Modification Outstanding Recorded Investment		$ 121
Post-Modification Outstanding Recorded Investment		$ 121
Commercial And Industrial [Member] \| Term-Out Line Of Credit [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	1	1
Pre-Modification Outstanding Recorded Investment	$ 180	$ 20
Post-Modification Outstanding Recorded Investment	$ 180	$ 20
Residential Mortgages [Member] \| Extension Of Maturity [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	2	1
Pre-Modification Outstanding Recorded Investment	$ 254	$ 95
Post-Modification Outstanding Recorded Investment	$ 272	$ 95
Residential Mortgages [Member] \| Extension Of Maturity And Interest Rate Reduction [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract		1
Pre-Modification Outstanding Recorded Investment		$ 109
Post-Modification Outstanding Recorded Investment		$ 109
Commercial Real Estate Mortgages [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract
Pre-Modification Outstanding Recorded Investment
Post-Modification Outstanding Recorded Investment
Commercial Real Estate Mortgages [Member] \| Extension Of Maturity [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	3
Pre-Modification Outstanding Recorded Investment	$ 5,073
Post-Modification Outstanding Recorded Investment	$ 5,073
Commercial Real Estate Mortgages [Member] \| Combination Of Concessions [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	1
Pre-Modification Outstanding Recorded Investment	$ 4,179
Post-Modification Outstanding Recorded Investment	$ 3,397
Home Equities [Member] \| Deferral Of Principal [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	1
Pre-Modification Outstanding Recorded Investment	$ 175
Post-Modification Outstanding Recorded Investment	$ 175
Home Equities [Member] \| Extension Of Maturity And Interest Rate Reduction [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	1
Pre-Modification Outstanding Recorded Investment	$ 20
Post-Modification Outstanding Recorded Investment	$ 20
Consumer And Other Loans [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract
Pre-Modification Outstanding Recorded Investment
Post-Modification Outstanding Recorded Investment

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Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953676-111524

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