Loans And Allowance For Loan Losses (Summary Of Activity In The Allowance For Loan Losses) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of period	$ 155,932	$ 151,532	$ 156,532
Provision for Loan, Lease, and Other Losses	45,244	36,318	28,727
Loans charged off	55,179	50,978	51,050
Less recoveries	13,535	19,060	17,323
Allowance for Loan and Lease Losses Write-offs, Net	41,644	31,918	33,727
Balance at end of period	159,532	155,932	151,532
Commercial Portfolio Segment [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of period	91,361	82,086	89,622
Provision for Loan, Lease, and Other Losses	2,327	4,898	(9,319)
Loans charged off	2,538	3,258	4,057
Less recoveries	2,554	7,635	5,840
Allowance for Loan and Lease Losses Write-offs, Net	(16)	(4,377)	(1,783)
Balance at end of period	93,704	91,361	82,086
Personal Banking Portfolio Segment [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of period	64,571	69,446	66,910
Provision for Loan, Lease, and Other Losses	42,917	31,420	38,046
Loans charged off	52,641	47,720	46,993
Less recoveries	10,981	11,425	11,483
Allowance for Loan and Lease Losses Write-offs, Net	41,660	36,295	35,510
Balance at end of period	$ 65,828	$ 64,571	$ 69,446