Derivative Instruments (Summary Of The Effects Of Derivative Instruments On Consolidated Statements Of Income) (Details) - Not Designated as Hedging Instrument [Member] - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on Derivative Instruments, Net, Pretax	$ 628	$ 332	$ 3,910	$ 1,193
Other Non-Interest Income [Member] | Interest Rate Swaps [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on Derivative Instruments, Net, Pretax	692	702	2,924	1,301
Other Non-Interest Income [Member] | Credit Risk Participation Agreements [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on Derivative Instruments, Net, Pretax	(7)	7	173	18
Other Non-Interest Income [Member] | Foreign Exchange Contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on Derivative Instruments, Net, Pretax	(120)	51	62	(24)
Loans Fees And Sales [Member] | Mortgage Loan Commitments [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on Derivative Instruments, Net, Pretax	(50)	(114)	99	408
Loans Fees And Sales [Member] | Mortgage Loan Forward Sale Contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on Derivative Instruments, Net, Pretax	0	8	6	70
Loans Fees And Sales [Member] | Forward TBA Contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on Derivative Instruments, Net, Pretax	$ 113	$ (322)	$ 646	$ (580)