Goodwill And Other Intangible Assets (Amortizing Intangible Assets) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	$ 194,532	$ 194,532
Accumulated amortization	(186,112)	(178,260)
Net carrying amount	8,420	16,272
Goodwill impairment	0	0
Core Deposit Intangibles [Member]
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	166,518	166,518
Accumulated amortization	(158,444)	(151,157)
Net carrying amount	8,074	15,361
Customer Relationships And Other Intangibles [Member]
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	28,014	28,014
Accumulated amortization	(27,668)	(27,103)
Net carrying amount	$ 346	$ 911