Derivative Instruments (Effect Of Fair Value Hedges On Consolidated Statements Of Income) (Details) - Derivatives not designated as hedging instruments - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Derivative [Line Items]
Gain (Loss) Recognized in Income	$ 934	$ (1,785)
Interest rate contracts \| Other non-interest income
Derivative [Line Items]
Gain (Loss) Recognized in Income	7	(1)
Mortgage derivatives \| Mortgage banking income
Derivative [Line Items]
Gain (Loss) Recognized in Income	$ 927	$ (1,784)

Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5618551-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (a),(c),(d),(e)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624171-113959

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Balance Type:	credit
Period Type:	duration