Derivative Instruments (Effect Of Fair Value Hedges On Consolidated Statements Of Income) (Details) - Not Designated As Hedging Instruments [Member] - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Derivative [Line Items]
Amount of Gain (Loss) Recognized in Income on Derivative	$ 1,983	$ 1,143	$ (602)
Interest Rate Contracts [Member] | Other Non-Interest Income [Member]
Derivative [Line Items]
Amount of Gain (Loss) Recognized in Income on Derivative	76	44	460
Mortgage Derivatives [Member] | Mortgage Banking Income [Member]
Derivative [Line Items]
Amount of Gain (Loss) Recognized in Income on Derivative	$ 1,907	$ 1,099	$ (1,062)