Intangible Assets (Summary Of Intangible Assets and Accumulated Amortization Included In The Consolidated Statements of Condition) (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2018 USD ($) branch	Dec. 31, 2017 USD ($)
Intangible Assets [Line Items]
Gross Carrying Amount	$ 240,637	$ 244,137
Accumulated Amortization	(72,682)	(59,748)
Net Carrying Value	$ 167,955	184,389
Number of branches divested | branch	2
State banking licenses
Intangible Assets [Line Items]
Net Carrying Value	$ 300
Core deposit intangibles
Intangible Assets [Line Items]
Gross Carrying Amount	157,150	160,650
Accumulated Amortization	(18,146)	(8,176)
Net Carrying Value	139,004	152,474
Customer relationships
Intangible Assets [Line Items]
Gross Carrying Amount	77,865	77,865
Accumulated Amortization	(53,211)	(50,777)
Net Carrying Value	24,654	27,088
Other
Intangible Assets [Line Items]
Gross Carrying Amount	5,622	5,622
Accumulated Amortization	(1,325)	(795)
Net Carrying Value	$ 4,297	$ 4,827