Derivatives (Summary Of Types Of Derivatives And Gains (Losses) Recorded) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Interest Rate Contracts
Derivative Instruments, Gain (Loss) [Line Items]
Derivative gains (losses)	$ (10,705)	$ (453)	$ (2,816)
Interest Rate Contracts | Interest Rate Lock Commitments | Mortgage Banking Revenue
Derivative Instruments, Gain (Loss) [Line Items]
Derivative gains (losses)	676	445	763
Interest Rate Contracts | Interest Rate Forward Sales Commitments | Mortgage Banking Revenue
Derivative Instruments, Gain (Loss) [Line Items]
Derivative gains (losses)	(11,024)	(3,730)	(4,752)
Interest Rate Contracts | Interest Rate Swap | Other Income
Derivative Instruments, Gain (Loss) [Line Items]
Derivative gains (losses)	(1,451)	1,497	162
Foreign Exchange Contract | Other Income
Derivative Instruments, Gain (Loss) [Line Items]
Derivative gains (losses)	$ 1,094	$ 1,335	$ 1,011