Accumulated Other Comprehensive Loss (Schedule Of Amounts Reclassified Out of Accumulated Other Comprehensive Income) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net securities gains reclassified into earnings			$ 4,276	$ 3,978
Related income tax expense	$ (7,003)	$ (6,577)	(21,463)	(18,745)
Net income	13,932	13,232	44,646	37,476
Unrealized Gain (Losses) on Securities Available-for-Sale | Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net securities gains reclassified into earnings	0	(2,668)	(4,276)	(3,513)
Related income tax expense	0	(985)	(1,578)	(1,298)
Net income	$ 0	$ 1,683	$ 2,698	$ 2,215