Investment Securities (Gross Realized Gains And Losses On Sales Of Available-For-Sale Securities) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Investment Holdings [Line Items]
Gains	$ 135	$ 1,241	$ 3,763
Losses	108	383	841
US Treasury and Government [Member]
Investment Holdings [Line Items]
Gains	0	0	13
Losses	0	0	0
Obligations Of States And Political Subdivisions
Investment Holdings [Line Items]
Gains	0	971	631
Losses	9	0	0
Residential Mortgage-Backed Securities And Collateralized Mortgage Obligations
Investment Holdings [Line Items]
Gains	135	270	3,119
Losses	$ 99	$ 383	$ 841

This item represents the gross profit realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27357-111563

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