Fair Value Measurements (Summary Of Gains And Losses On Level 3 Assets And Liabilities) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Gains and Losses included in earnings for Level 3 assets & liabilities [Line Items]
Total gains or losses included in earnings	$ 17	$ (2,814)	$ (2,297)	$ (3,255)
Change in unrealized gains or losses relating to assets still held	920	(2,043)	(1,773)	(2,992)
Loans Fees And Sales [Member]
Gains and Losses included in earnings for Level 3 assets & liabilities [Line Items]
Total gains or losses included in earnings	(32)	19	522	527
Change in unrealized gains or losses relating to assets still held	871	790	871	790
Other Non-Interest Income [Member]
Gains and Losses included in earnings for Level 3 assets & liabilities [Line Items]
Total gains or losses included in earnings	1	(23)	11	(58)
Change in unrealized gains or losses relating to assets still held	1	(23)	11	(58)
Investment Securities Gains (Losses), Net [Member]
Gains and Losses included in earnings for Level 3 assets & liabilities [Line Items]
Total gains or losses included in earnings	48	(2,810)	(2,830)	(3,724)
Change in unrealized gains or losses relating to assets still held	$ 48	$ (2,810)	$ (2,655)	$ (3,724)